SECTION 2 Diagnostic Methods

Contents Diagnostic Methods..........................................................................2-1 Overview .......................................................................................2-1 Diagnostic Tools...............................................................................2-2 Scan Tool Setup and Functionality..................................................2-3 Vehicle Check And Preparation.......................................................2-4 Visual Checks ...............................................................................2-4 Vehicle Preparation ......................................................................2-4 Quick Test Description.....................................................................2-5 Clear the Continuous Diagnostic Trouble Codes (DTCs) and Reset the Emission Monitors Information in the Powertrain Control Module (PCM) ..............................................2-8 Resetting The Keep Alive Memory (KAM) ......................................2-9 On Board System Readiness (OSR) Test.....................................2-10 Output State Control (OSC)...........................................................2-11 One Touch Integrated Start System.......................................2-11 Output Test Mode (OTM)...............................................................2-12 Parameter Identification (PID)........................................................2-13 Freeze Frame Data........................................................................2-22

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SECTION 2 Diagnostic Methods

Contents (Continued) Flash Electrically Erasable Programmable Read Only Memory (EEPROM)...................................................................2-24 Diagnostic Monitoring Test Results Mode 6..................................2-27 On Board Diagnostic (OBD) Drive Cycle ......................................2-28 Intermittent Diagnostic Techniques................................................2-34 Recreating the Fault ...................................................................2-34 Accumulating PCM Data ............................................................2-34 Peripheral Inputs ........................................................................2-35 Comparing PCM Data ................................................................2-35 Adaptive Fuel Diagnostic Trouble Code (DTC) Diagnostic Techniques ................................................................................2-36

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Table of Contents

Diagnostic Methods Overview When following powertrain diagnostics on vehicles with on board diagnostic (OBD), the system may be checked by an off-board tester referred to as a scan tool. This section contains information for carrying out diagnostics with a scan tool. A scan tool has certain generic capabilities that are standard across the automotive industry in the United States and Canada. All functions are selected from a menu. Refer to the instruction manual provided by the tool manufacturer.

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Diagnostic Methods

Diagnostic Tools

Below is an equipment list with corresponding part numbers: REQUIRED EQUIPMENT: • Vehicle Communication Module (VCM) and Integrated Diagnostic System (IDS) software with appropriate hardware, or equivalent scan tool with functionality described under Scan Tool Setup and Functionality. • Rotunda Smoke Machine, Fuel Evaporative Emission System Tester 218-00001 (522) or equivalent. RECOMMENDED EQUIPMENT: • Rotunda Vacuum/Pressure Tester 164-R0253 or equivalent. Range 0-101.3 kPa (0-30 in-Hg.) Resolution 3.4 kPa (1 in-Hg.) • Fuel Pressure Test Kit 310-D009 (D95L-7211A) or equivalent. • Fuel Pressure Test Adapter 310-180 or equivalent. • Digital Multimeter (DMM) FLU77-4 or equivalent. • Adjustable Ignition Spark Tester THX404 or equivalent. • Non-powered test lamp.

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Scan Tool Setup and Functionality

Connect the scan tool to the data link connector (DLC) for communication with the vehicle. The DLC is located in the driver side compartment under the steering column. It is attached to the instrument panel and accessible from the driver seat. The DLC is rectangular in design and capable of accommodating up to 16 terminals. The connector has keying features to allow easy connection. The required scan tool functions are described below: — monitor, record, and playback of parameter identification (PID) — freeze frame PID data — diagnostic test modes; self-test, clear diagnostic trouble codes (DTCs) — output state control — output test mode — resetting keep alive memory (KAM) — diagnostic monitoring test results (mode 6) for on board diagnostic (OBD) monitors — on board system readiness (OBD monitor completion status) Some of these functions are described in this section. Refer to the scan tool manufacturer’s instruction manual for specific information on scan tool setup and operation.

International Standards Organization (ISO) 14229 DTC Descriptions The ISO 14229 DTC is a set of common requirements for diagnostic systems. The scan tool displays a failure type and a status type with the DTC. The types display additional information on the scan tool for the condition that set the DTC. For a list of failure type descriptions, refer to Section 1, Powertrain Control Software, International Standards Organization (ISO) 14229 Diagnostic Trouble Code (DTC) Descriptions.

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Vehicle Check And Preparation

Before using the scan tool to carry out any test, refer to the important Safety Notice located at the beginning of this manual and the necessary visual checks listed below.

Visual Checks • Inspect the air cleaner and inlet duct. • Check all engine vacuum hoses for damage, leaks, cracks, kinks, and proper routing. • Check the electronic engine control (EEC) system wiring harness for proper connections, bent or broken pins, corrosion, loose wires, and proper routing. • Check the powertrain control module (PCM), sensors, and actuators for physical damage. • Check the engine coolant for proper level and mixture. • Check the transmission fluid level and quality. • Make all necessary repairs before continuing with the quick test. Refer to Quick Test in this section for additional information.

Vehicle Preparation • Carry out all safety steps required to start and run vehicle tests. Apply the parking brake, place the gear selector lever firmly into the PARK position on automatic transmission vehicles or NEUTRAL on manual transmission vehicles, and block the drive wheels. • Turn off all electrical loads such as radios, lamps, A/C, blower, and fans. • Start the engine (if the engine runs) and bring it up to the normal operating temperature before running the quick test.

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Quick Test Description

Quick Test The quick test is divided into 3 specialized tests: (1) Key On Engine Off (KOEO) On Demand Self-Test (2) Key On Engine Running (KOER) On Demand Self-Test (3) Continuous Memory Self-Test The quick test checks the integrity and function of the electronic engine control (EEC) system and outputs the test results when requested by the scan tool. The quick test also provides a quick check of the powertrain control system, and is usually carried out at the start of each diagnostic procedure with all accessories off. The quick test is also carried out at the end of most pinpoint tests for verification of the repair and to make sure no other concerns are incurred while repairing a previous concern. A system pass is displayed when no diagnostic trouble codes (DTCs) are output and a scan tool communication error does not exist. System pass means that hardware monitored by the powertrain control module (PCM) is functioning within the normal operating limits. Only a system pass, a DTC, or an incomplete on board diagnostic (OBD) drive cycle is displayed. For applications that use a stand-alone transmission control module (TCM) the PCM does not output TCM DTCs. For TCM self-test and diagnostics, refer to the Workshop Manual Section 307-01 Automatic Transmission.

Key On Engine Off (KOEO) On Demand Self-Test The KOEO on demand self-test is a functional test of the PCM carried out on demand with the key on and the engine off. This test carries out checks on certain sensor and actuator circuits. A concern must be present at the time of testing for the KOEO self-test to detect the concern. When a concern is detected, a DTC is output on the data link at the end of the test as requested by the scan tool.

Key On Engine Running (KOER) On Demand Self-Test The KOER on demand self-test is a functional test of the PCM carried out on demand with the key on, the engine running and the vehicle stopped. A check of certain inputs and outputs is made during operating conditions and at a normal operating temperature. The brake pedal position, transmission control, and the power steering tests are part of the KOER on demand self-test and must be carried out during this operation if applicable. These are described below. A concern must be present at the time of testing for the KOER on demand self-test to detect the concern. When a concern is detected, a DTC is output on the data link at the end of the test as requested by the scan tool.

Brake Pedal Position (BPP) Test The BPP test checks the ability of the EEC system to detect a change of state in the BPP switch. The brake pedal is briefly applied and released on all vehicles equipped with a BPP input. This is done during a KOER on demand self-test.

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Quick Test Description

Power Steering Pressure (PSP) Test The PSP test checks the ability of the EEC system to detect a change in the power steering system fluid pressure. The steering wheel is briefly turned at least 1/4 of a revolution on vehicles equipped with a PSP switch or sensor. This is done during a KOER on demand self-test.

Transmission Control Switch (TCS) Test The TCS test checks the ability of the EEC system to detect a change of state in the TCS. The switch is briefly cycled on all vehicles equipped with a TCS input. This is done during a KOER on demand self-test.

Continuous Memory Self-Test The continuous memory self-test is a functional test of the PCM carried out under any condition (engine running or off) with the key on. Unlike the KOEO and KOER self-tests, which can only be activated on demand, the continuous self-test is always active. A concern does not need to be present when accessing continuous memory self-test DTCs, making the test valuable when diagnosing intermittent concerns. The vehicle may need to be driven or the OBD drive cycle completed to allow the PCM to detect a concern. Refer to On Board Diagnostic (OBD) Drive Cycle in this section for more information. When a concern is stored in memory, a DTC is output on the data link when requested by the scan tool. There are two types of continuous DTCs. The first type is an emission-related code which illuminates the malfunction indicator lamp (MIL) in the instrument cluster. The second is a non-emission related, non-MIL DTC which does not illuminate the instrument cluster indicator. For emission-related MIL DTCs, the PCM stores the DTC in continuous memory when a concern is detected for the first time. At this point the DTC does not illuminate the MIL and is considered a pending code. The purpose of pending codes is to assist in repair verification by reporting a pending DTC after one drive cycle. If the same concern is detected after the next drive cycle, the emission-related MIL code illuminates the MIL and sets both a confirmed MIL DTC and a permanent DTC. The MIL remains illuminated even if the concern is intermittent. A permanent DTC is stored until three consecutive passing drive cycles have been completed after a repair and the MIL turns off, or after a request to clear DTCs has been made using the scan tool and the next monitoring cycle has completed and passed for that DTC. Confirmed emission-related MIL DTCs and any non-emission related, non-MIL DTCs are erased approximately 40 vehicle warm-up cycles after the concern was last detected, or if the DTCs are cleared by the scan tool. Pending emission-related MIL DTCs that never detect a concern on a second consecutive drive cycle (and never light the MIL) are not retained in memory for any number of vehicle warm-up cycles; they are immediately cleared when the next monitoring cycle has completed and passed for that DTC, or until a request to clear DTCs has been made by the scan tool. Any scan tool that meets OBD requirements can access the continuous memory to retrieve emission-related MIL DTCs. However, not all scan tools access pending and non-emission related, non-MIL DTCs in the same way. 2011Powertrain Control/Emissions Diagnosis, 8/2010

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Quick Test Description

During most diagnostic procedures in this manual, it is required that all DTCs be retrieved and cleared. Permanent DTCs cannot be directly cleared by the scan tool. When a scan tool clears DTCs, pending and confirmed DTCs are immediately cleared. Permanent DTCs will not clear until the next monitoring cycle has completed and passed for that DTC. For additional information, refer to Section 1, Powertrain Control Software, Permanent Diagnostic Trouble Code (DTC).

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Diagnostic Methods

Clear the Continuous Diagnostic Trouble Codes (DTCs) and Reset the Emission Monitors Information in the Powertrain Control Module (PCM) Description All on board diagnostic (OBD) scan tools support the clearing of continuous DTCs and resetting of emission monitors information in the PCM. The clearing of the continuous DTCs allows the scan tool to command the PCM to clear and reset all emission-related diagnostic information. On some vehicles, DTC P1000 is stored in the PCM until all the OBD system monitors or components have been tested to satisfy a drive cycle without any other concerns occurring. For more information about a drive cycle, refer to On Board Diagnostic (OBD) Drive Cycle in this section. The following events occur when the continuous DTCs and the emission monitors information is cleared from the PCM: • the number of DTCs is reset • the DTCs are cleared (on vehicles with permanent DTCs, additional vehicle operation is required to complete and pass the appropriate monitors to complete the clearing of permanent DTCs) • the freeze frame data is cleared • the diagnostic monitoring test results are reset • the status of the OBD system monitors is reset

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Resetting The Keep Alive Memory (KAM)

Description Resetting the KAM returns the powertrain control module (PCM) memory to its default setting. Adaptive learning contents such as adaptive airflow, idle speed, refueling event, and fuel trim are included. Clear the continuous diagnostic trouble codes (DTCs) in the PCM and reset the emission monitors information, is part of a KAM reset. Refer to Clear the Continuous Diagnostic Trouble Codes (DTCs) and Reset the Emission Monitors Information in the Powertrain Control Module (PCM) in this section. Both can be useful in post-repair testing. After the KAM has been reset, the vehicle may exhibit certain driveability concerns. It is necessary to allow the engine to idle at normal operating temperature with the A/C off for 2 minutes. Then drive the vehicle to allow the PCM to learn the values for optimum driveability and performance. This function may not be supported by all scan tools. Refer to the scan tool manufacturer’s instruction manual. If an error message is received or the scan tool does not support this function, disconnecting the battery ground cable for a minimum of 5 minutes may be used as an alternative procedure on some vehicles.

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Diagnostic Methods

On Board System Readiness (OSR) Test

Description All on board diagnostic (OBD) scan tools display the on board system readiness (OSR) test. The OSR displays the supported monitors on the vehicle and the status of all monitors (complete or not complete) at that time. Fuel, misfire, and comprehensive component monitors (CCMs) run continuously and always display a YES status. Clearing the continuous diagnostic trouble codes (DTCs) and resetting the emission monitors information in the powertrain control module (PCM), or resetting the keep alive memory (KAM) causes the non-continuous monitors to change to a NO status. A detailed description of completing the OBD monitors is found in this section. Refer to On Board Diagnostic (OBD) Drive Cycle.

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Output State Control (OSC)

Description

WARNING: Safety must be observed when using OSC. Failure to follow these instructions may result in personal injury. The OSC aids in diagnosing output actuators associated with the powertrain control module (PCM) for the engine. This mode allows the technician to command the individual actuator state. For example, the output can be enabled or disabled, the duty cycle or the angle of the output can be increased or decreased. OSC is used to help test the electrical, hydraulic or mechanical components of the vehicle. This function is supported by the vehicle strategy but may not be present on all vehicles or available on all scan tools. Retrieve the continuous codes and carry out a key on, engine off (KOEO) and key on, engine running (KOER) on demand self-test before using any OSC. Any diagnostic trouble codes (DTCs) related to the transmission range (TR) sensor, output shaft speed (OSS) sensor or the vehicle speed sensor (VSS) must be fixed or the PCM does not allow the OSC to operate. Each OSC function has a unique set of vehicle operating requirements that the technician is required to meet before operating the OSC. If the vehicle requirements are not met while commanding the OSC value, an error message appears. When the error message is received, OSC is canceled. To confirm the scan tool sent the OSC value and the PCM has accepted the OSC substitution, a corresponding parameter identification (PID) for each OSC parameter must be monitored.

One Touch Integrated Start System Some vehicles are equipped with one touch integrated start system. It may be necessary to disable the one touch integrated start system to carry out diagnostic procedures that require extended cranking. Connect the scan tool, access the PCM and select the one touch integrated start system control PID to disable the system.

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Diagnostic Methods

Output Test Mode (OTM)

Description

WARNING: Safety must be observed when using OTM. — When all outputs are on, the electric fuel pump is briefly energized. Make sure the fuel system is intact and is not being repaired at this time. — When low speed or high speed fan control(s) are turned on, make sure the fan blades are clear of any obstruction. Failure to follow these instructions may result in personal injury. The OTM aids in diagnosing output actuators associated with the powertrain control module (PCM). This mode allows the technician to energize and de-energize most of the system output actuators on command. When entering OTM, the outputs can be turned off and on without activating the fan control. The low and high speed fan controls may be turned on separately without energizing the other outputs. This function is supported by each vehicle strategy and may not be available on all scan tools. As a safety precaution, OTM defaults to the off state after 10 minutes, and the fuel pump off state after approximately 7-10 seconds. OTM also turns off after the vehicle is started or after cycling the key OFF then ON.

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Parameter Identification (PID)

Description The PID mode allows access to powertrain control module (PCM) information. This includes analog and digital signal inputs and outputs along with calculated values and the system status. There are two types of PID lists available and both are used throughout this manual. The first is the generic (J1979) OBD PID list. This is a standard set of PIDs that all scan tools must be able to access. The second is a Ford specific (J2190) list which can be accessed by an appropriate scan tool. When accessing any of these PIDs, the values are continuously updated. The generic or Ford PID list provides definitions and values in appropriate units. For more information, refer to the Society of Automotive Engineers (SAE) document J2205.

Generic OBD PID List An X in the Freeze Frame column denotes both a mode 1 and mode 2 PID (real time and freeze frame). Freeze Frame

Acronym

Description

Measurement Units

X

APP

D

Accelerator Pedal Position D

%

X

APP

E

Accelerator Pedal Position E

%

X

APP

F

Accelerator Pedal Position F

X

BARO

Barometric Pressure

X

CATEMP11

Catalyst Temperature Bank 1, Sensor 1

Degrees

X

CATEMP12

Catalyst Temperature Bank 1, Sensor 2

Degrees

X

CATEMP21

Catalyst Temperature Bank 2, Sensor 1

Degrees

X

CATEMP22

Catalyst Temperature Bank 2, Sensor 2

Degrees

X

CLRDIST

Distance Since Codes Cleared

Km/mi

X

CLRWRMUP

Number of Warm Ups Since DTCs Cleared

Units

X

ECT

Engine Coolant Temperature

X

EGRPCT

Commanded EGR

X

EGR

EGR Error

%

X

EVAP VP

Evaporative System Vapor Pressure

Pa

X

EQ

Commanded Equivalence Ratio

Unit

X

FLI

Fuel Level Input

X

FRP

Fuel Rail Pressure

X

FUEL SYS1

Fuel System Feedback Control Status Bank 1

Open Loop / Closed Loop

X

FUEL SYS2

Fuel System Feedback Control Status Bank 2

Open Loop / Closed Loop

X

IAT

Intake Air Temperature

Degrees

X

LOAD

Calculated Engine Load

%

X

LOAD

Absolute Load Value

%

X

LONGFT1

Current Bank 1 Fuel Trim Adjustment (kamref1) From Stoichiometry Which Is Considered Long Term

%

ERR RAT

a

ABS

% kPa

Degrees %

% kPa

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Parameter Identification (PID)

Freeze Frame

a

Acronym

Description

Measurement Units

X

LONGFT2

Current Bank 2 Fuel Trim Adjustment (kamref2) From Stoichiometry Which Is Considered Long Term

X

MAF

Mass Air Flow Rate

g/s-lb/min

X

MAP

Manifold Absolute Pressure

Volts/kPa/ PSI/inHg

X

MIL

Distance Traveled with MIL ON

Kilometer

X

O2S11

Bank 1 Upstream Oxygen Sensor (11)

Volts

X

O2S12

Bank 1 Downstream Oxygen Sensor (12)

Volts

X

O2S13

Bank 1 Downstream Oxygen Sensor (13)

Volts

X

O2S21

Bank 2 Upstream Oxygen Sensor (21)

Volts

X

O2S22

Bank 2 Downstream Oxygen Sensor (22)

Volts

X

O2S23

Bank 2 Downstream Oxygen Sensor (23)

OBDSUP

On Board Diagnostic System

X

PTO

Power Take-Off Status

On/Off

X

RPM

Revolutions Per Minute

RPM

X

RUNTM

Run Time

X

SHRTFT1

Current Bank Fuel Trim Adjustment (lambse1) From Stoichiometry Which Is Considered Short Term

%

X

SHRTFT2

Current Bank 2 Fuel Trim Adjustment (lambse1) From Stoichiometry Which Is Considered Short Term

%

X

SPARKADV

Spark Advance Requested

Degrees

X

SPARK ACTUAL

Spark Advance Actual

Degrees

X

TAC PCT

Commanded Throttle Actuator

%

X

TP

Throttle Position

%

X

TP REL

Relative Throttle Position

%

VSS

Vehicle Speed Sensor

DIST

%

Volts OBD II OBD I OBD Combination of or None

Seconds

km/h-mph

Percent engine load adjusted for atmospheric pressure.

Ford PID List Note: This is not a complete list of Ford PIDs available. This is a list of Ford PIDs in this manual.

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Parameter Identification (PID)

PID AAT AAT

Description

Ford Units

Ambient Air Temperature V

Degrees

Ambient Air Temperature Voltage

Volts

ACP V

A/C Pressure Sensor Voltage

ACP PRESS

A/C Pressure Sensor Pressure

Pressure

APP

Accelerator Pedal Position

Percent

APP1

Accelerator Pedal Position 1

Volts

APP2

Accelerator Pedal Position 2

Volts

APP3

Accelerator Pedal Position 3

Volts

APP

MAXDIFF

Maximum Difference between APP1 and APP2

APP

MODE

Accelerator Pedal Position Mode

Volts

Degrees Pedal Position

AXLE

Axle Ratio

Ratio

B+

Battery Voltage

Volts

BARO

Barometric Pressure Sensor

BOO

Brake Pedal Position (BPP) Switch

On/Off

BOO1

Brake Pedal Position (BPP) Switch

On/Off

BOO2

Brake Pressure Applied

On/Off

BPA

Brake Pressure Applied (BPA)

On/Off

BPP/BOO

Brake Pedal Position (BPP) Switch

On/Off

CAC T

Charge Air Cooler Temperature

CAC V

Charge Air Cooler Voltage

CAT EVAL

Catalyst Evaluated

CHT

Cylinder Head Temperature Input

CLRDIST

Distance Since DTCs Cleared

Miles

CLRWRMUP

Number of Warm-ups Since DTCs Cleared

Count

CPP BOT

Clutch Pedal at or Near Bottom of Travel

Yes/No

CPP

Clutch Pedal Position Switch Input

On/Off

CPP/PNP

Clutch Pedal Position/Park Neutral Position Switch Input

DECHOKE

Crank Fueling Disabled

DPFEGR

Differential Pressure Feedback EGR Input

ECT

Engine Coolant Temperature Input

EGRMC1F

EGR Motor Control Fault

Yes/No

EGRMC2F

EGR Motor Control Fault

Yes/No

EGRMC3F

EGR Motor Control Fault

Yes/No

EGRMC4F

EGR Motor Control Fault

Yes/No

EGRMDSD

Electric EGR Motor Commanded in Steps

On/Off

EGRPCT

Commanded EGR

Percent

EGRVR

EGR Valve Vacuum Control

Percent

EGR

EVAL

EGR Evaluated

Yes/No

EGR

STEP

EGR Valve Motor Position

EONV RDY

EVAP Monitor Test Ready at Next Key Off

Frequency/Pressure

Degrees F Volts Yes/No Volt/Degrees F

Neutral/Drive Yes/No Volts Volts/Degrees F

Position Ready/Not Ready

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Parameter Identification (PID)

PID

Description

EOT

Ford Units

Engine Oil Temperature Sensor Input

Volts/Degrees F

EOT F

Engine Oil Temperature Sensor Fault

Fault/No Fault

EQ

RAT11

Equivalence Ratio Lambda Bank 1, Sensor 1

EQ

RAT21

Equivalence Ratio Lambda Bank 2, Sensor 1

Ratio Ratio

ETC ACT

Electronic Throttle Control Actual

Degrees

ETC DSD

Electronic Throttle Control Desired

Degrees

ETC TRIM

Electronic Throttle Control Trim

Degrees

EVAP020C

Evaporative Emissions Monitor

Yes/No

EVAP020D

Evaporative Emissions Monitor

Allow/Disallow

EVAP020R

Evaporative Emissions Monitor

Ready/Not Ready

EVAPCP

Evaporative Emissions Canister Purge Valve

Percent/On/Off

Evaporative Emissions Canister Purge Vent Control

Percent/On/Off

Evaporative Emissions Canister Purge Vent Fault

Fault/No Fault

EVAPCV EVAPCV

F

EVAPSOAK

Evaporative Emissions Monitor Soak Conditions are Met

Yes/No

EVAPSTA

Evaporative Emissions Monitor Completed Cycle

Status

EVAP ACTIVE EVAP COMLIN

Evaporative Emissions Activation Switch Position at Start Detection F

Evaporative Emissions Module Communication Line Status

Yes/No Fault/No Fault

EVAP EVAL

Evaporative Emissions Monitor Evaluated

EVAP SWITCH

Evaporative Emissions Actual Switch Position

EVMV

Electronic Vapor Management Valve Commanded Current

Current

FAN

Engine Cooling Fan Operation

On/Off

FANDC

Variable Speed Fan Duty Cycle

Percent

FAN DSD

Fan Speed Desired

Percent

FANSS

Fan Speed Sensor Signal

FANVAR

Variable Speed Fan Output

FANVAR F

Variable Speed Fan Output Fault

FCIL

Fuel Cap Indicator Light

On/Off

FF INF

Inferred Flex Fuel

Percent

FLI

Fuel Level Indicator Input

Percent

FP

Fuel Pump Duty Cycle

Percent

FP

Fuel Pump

On/Off

FPM

Fuel Pump Secondary Monitor

Percent/On/Off

FPM2

Fuel Pump Secondary 2 Monitor

Percent/On/Off

FPM STAT

Fuel Pump Monitor Status

Fault/No Fault

FRP

Fuel Rail Pressure Input

Volts/Pressure

FRP DSD

Fuel Rail Pressure Desired

FRT

Fuel Rail Temperature

FTP

Yes/No Open/Closed

RPM Percent Fault/No Fault

Pressure Degrees F/Volts

Fuel Tank Pressure Input

Volts/Pressure

FTP

H2O

Fuel Tank Pressure Input

Pressure

FTP

INF

Inferred Fuel Tank Pressure

Pressure

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Parameter Identification (PID)

PID

Description

Ford Units

FUELPW1

Injector Pulse Width Bank 1

Time

FUELPW2

Injector Pulse Width Bank 2

FUELSYS

Fuel System Status

F VCV

Fuel Volume Control Valve

GEAR

Transmission Gear Status

HFC

High Speed Fan Control

HTR11

Bank 1 Sensor 1 HO2S Heater Control

On/Off

HTR11F

Bank 1 Sensor 1 HO2S Heater Circuit Fault

Yes/No

HTR12

Bank 1 Sensor 2 HO2S Heater Control

HTR12F

Bank 1 Sensor 2 HO2S Heater Circuit Fault

HTR13

Bank 1 Sensor 3 HO2S Heater Control

On/Off

HTR21

Bank 2 Sensor 1 HO2S Heater Control

On/Off

HTR21F

Bank 2 Sensor 1 HO2S Heater Circuit Fault

HTR22

Bank 2 Sensor 2 HO2S Heater Control

HTR22F

Bank 2 Sensor 2 HO2S Heater Circuit Fault

Fault/No Fault

HTRCM11

Bank 1 Sensor 1 O2S Heater Circuit Current

Current

HTRCM12

Bank 1 Sensor 2 O2S Heater Circuit Current

Current

HTRCM21

Bank 2 Sensor 1 O2S Heater Circuit Current

Current

HTRCM22

Bank 2 Sensor 2 O2S Heater Circuit Current

Current

HTRX1

HO2S Sensor 1 (Upstream) Heater Control

On/Off

HTRX2

HO2S Sensor 2 (Downstream) Heater Control

On/Off

HO2S11

Bank 1 Sensor 1 HO2S Input

Volts

HO2S12

Bank 1 Sensor 2 HO2S Input

Volts

HO2S13

Bank 1 Sensor 3 HO2S Input

Volts

HO2S21

Bank 2 Sensor 1 HO2S Input

Volts

HO2S22

Bank 2 Sensor 2 HO2S Input

Volts

IAC

Idle Air Control

IACTRIM

Short Term Airflow Trim

IAT

Intake Air Temperature Input

Degrees F/Volts

IAT2

Intake Air Temperature Sensor 2 Input

Degrees F/Volts

IGN R/S

Ignition Switch Run/Start

On/Off

IMRC

Intake Manifold Runner Control

On/Off

IMRC F

Intake Manifold Runner Control Fault

Yes/No

IMRC1M

Intake Manifold Runner Control Monitor Input Bank 1

IMRCM

Intake Manifold Runner Control Monitor Input

IMTV

Intake Manifold Tuning Valve Control

Percent

INJ1F-8F

Fuel Injector Primary Fault (Cylinders 1-8)

Yes/No

INJ9F-10F

Fuel Injector Primary Fault (Cylinders 9 and 10)

Yes/No

INJPWR M

Injectors Circuit Voltage Monitor

Time Open Loop/ Closed Loop Percent Gear On/Off

On/Off Fault/No Fault

Fault/No Fault On/Off

Percent Numeric Value

Volts Volts

Volts

(Continued)

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Parameter Identification (PID)

PID

Description

Ford Units

KNOCK

Knock Sensor Signal

Count

KNOCK1

Knock Sensor 1 Signal

Count

KNOCK2

Knock Sensor 2 Signal

Count

LFC

Low Speed Fan Control

On/Off

LOAD

Calculated Engine Load

Percent

LONGFT1

Long Term Fuel Trim Bank 1

Percent

LONGFT2

Long Term Fuel Trim Bank 2

Percent

MAF

Mass Airflow Rate Input

MAP

Intake Manifold Absolute Pressure

MAP

DMD

MIL MIL

Frequency/Volts/Mass Flow Frequency/Volts/ Pressure

Manifold Absolute Pressure Demanded

Pressure

Malfunction Indicator Lamp Control DIS

On/Off

Distance Since MIL was Activated

Miles

MISFIRE

Misfire Status

Yes/No

MP LRN

Learned Misfire Correction Profile

Yes/No

NM

Number of Misfires

NUM

Misfire Events During Latest Misfire Cycle

OUTDR TMP

Outdoor Air Temperature

O2BANK1

Bank 1 O2S Status

Rich/Lean

O2BANK2

Bank 2 O2S Status

Rich/Lean

O2S11

Count Count Degrees

Bank 1 Sensor 1 O2S Input

Volts

O2 DS

DISBL

Downstream Oxygen Sensor Fuel Control Disabled

Yes/No

O2 DS1

ERR

Downstream Closed Loop Input Error Bank 1

Volts

O2 DS2

ERR

Downstream Closed Loop Input Error Bank 2

Volts

O2S11

CUR

Bank 1 Sensor 1 Current

O2S11

HTR

Commanded Duty Cycle for the O2S11 Heater Output

Current

O2S11

IMPED

O2S11 Sensor Impedance

O2S11

READY

O2S11 Is Warm and Ready to Operate

O2S11

STAT

O2S11 Status

O2S11

TR

O2 Sensor Trim Circuit Resistance 11 NTK Sensor

Percentage Volts Yes/No Fault/No Fault Resistance

O2S12

Bank 1 Sensor 2 O2S Input

Volts

O2S21

Bank 2 Sensor 1 O2S Input

Volts

O2S21

CUR

Bank 2 Sensor 1 Current

O2S21

HTR

Commanded Duty Cycle for the O2S21 Heater Output

O2S21

IMPED

O2S21 Sensor Impedance

O2S21

READY

O2S21 Is Warm and Ready to Operate

O2S21

STAT

O2S21 Status

O2S21

TR

O2 Sensor Trim Circuit Resistance 21 NTK Sensor

O2S22

Bank 2 Sensor 2 O2S Input

O2S

Oxygen Sensor Circuits Evaluated

EVAL

Current Percentage Volts Yes/No Fault/No Fault Resistance Volts Yes/No

(Continued) 2011Powertrain Control/Emissions Diagnosis, 8/2010

Diagnostic Methods

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Parameter Identification (PID)

PID

Description

Ford Units

O2SHTR EVAL

Oxygen Sensor Heater Circuits Evaluated

Yes/No

OD CANCL

Overdrive Cancel Function

On/Off

OSS

Output Shaft Speed

OSS SRC

Output Shaft Speed

OTS STAT

One Touch Integrated Start System Status

Enabled/Disabled

PATSENABL

Passive Anti-Theft System Status

Enabled/Disabled

PCVHC

Positive Crankcase Ventilation Heater Control

PCVHC B

Positive Crankcase Ventilation Heater B

PSP

Power Steering Pressure Switch Input

PSP PSP

V

RPM RPM

Percent Percent High/Low

Power Steering Pressure Input

Volts

Power Steering Pressure Input

Volts

PTO

Power Take Off Status Input

On/Off

PTOLOAD

Power Take Off Engage Input

Yes/No

PTOIR V

Power Take Off RPM Select Input

PTOIL

Power Take Off Indicator Lamp Output

RO2FT1

Rear O2 Fuel Trim - Bank 1

Percentage

RO2FT2

Rear O2 Fuel Trim - Bank 2

Percentage

RPM

Engine Speed Based Upon CKP Input

RPM

RPMDSD

RPM Desired

RPM

SCBC

Supercharger Bypass Control

On/Off

SHRTFT

Short Term Fuel Trim

Percent

SHRTFT1

Short Term Fuel Trim Bank 1

Percent

SHRTFT2

Short Term Fuel Trim Bank 2

Percent

SPARKADV

Spark Advance

Degrees

SPKDUR

Spark Duration (Cylinders 1-8)

1-8

Volts On/Off

Time

STRT RLY

Starter Relay

SYNC

CMP and CKP Synchronized

TCIL

Transmission Control Indicator Lamp Clutch Control Status

On/Off

TCS

Transmission Control Switch (TCS)

Yes/No

TCSS

Transfer Case Speed Sensor

TFT

Transmission Fluid Temperature Input

TFTV

Transmission Fluid Temperature Input

Volts

THROTTLE CMD

Commanded Throttle Actuator Control

Percent

TIP PRES

BOOST

Throttle Inlet Pressure Measured (Boost Actual)

kPa/psi

TIP PRES

DSD

Throttle Inlet Pressure Desired (Boost Requested)

kPa/psi

TIP PRES

V

Throttle Inlet Pressure Sensor Voltage

TORQUE

Net Torque Into Torque Converter

TP

Throttle Position Input

TPCT

Lowest Closed Throttle Voltage

TP MAXDIFF

Maximum Angle Difference between TP1 and TP2

Enabled/Disabled Yes/No

MPH Volts/Degrees F

Volts Torque Volts/Percent Volts Degrees

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Diagnostic Methods

Parameter Identification (PID)

PID

Description

Ford Units

TPMODE

Throttle Position

TP1

Throttle Position 1 Voltage

TP2

Throttle Position 2 Voltage

TP B

Absolute Throttle Position B

TP1 ADP CLSD

Throttle Position 1 Adaption Voltage Closed Stop

Volts

TP1 ADP LIMP

Throttle Position 1 Adaption Voltage at Limp Home

Volts

TP1 ADP MINAIR

Throttle Position 1 Adaption Volt Minimum Air Flow

Volts

TP2 ADP CLSD

Throttle Position 2 Adaption Voltage Closed Stop

Volts

TP2 ADP LIMP

Throttle Position 2 Adaption Voltage at Limp Home

Volts

TQ

Torque Fuel/Spark Limiting Status

Text

CNTRL

Closed/Part/ Wide Open Throttle Volts Volts Percent

TR

Transmission Selector Position Input Status

TR1

Transmission Range Sensor 1

Open/Closed

TR2

Transmission Range Sensor 2

Open/Closed

TR3

Transmission Range Sensor 3

Open/Closed

TR4

Transmission Range Sensor 4

Open/Closed

TR V

Transmission Selector Position Input Status

TR D

Transmission Selector Position Input Status (Digital)

Binary

TRIP CNT

OBD II Trips Completed

Count

TURBO BP1 STAT

Turbocharger Bypass 1 Status

Fault/No Fault

TURBO BP2 STAT

Turbocharger Bypass 2 Status

Fault/No Fault

TURBO BPASS

Turbocharger Bypass Valve

Percent

Turbocharger Bypass Valve 2

Percent

TURBO BPASS

2

Position

Volts

TURBO OVER

Turbocharger Overboost Condition

Fault/No Fault

TURBO UNDER

Turbocharger Underboost Condition

Fault/No Fault

TWGATE STAT

Turbocharger Wastegate Status

Fault/No Fault

VCTADV

Variable Cam Timing Advance

Degrees

VCTADV2

Variable Cam Timing Advance 2

Degrees

VCTADVERR

Variable Cam Timing Advance Error

Degrees

VCTADVERR2

Variable Cam Timing Advance 2 Error

Degrees

VCTDC

Variable Cam Timing Advance Duty Cycle

Percent

VCTDC2

Variable Cam Timing Advance Duty Cycle

Percent

VCT EXH ACT1

Actual Exhaust B Camshaft Position Bank 1

Degrees

VCT EXH ACT2

Actual Exhaust B Camshaft Position Bank 2

Degrees

VCT EXH DC1

Exhaust B Camshaft Position Duty Cycle Bank 1

Percent

VCT EXH DC2

Exhaust B Camshaft Position Duty Cycle Bank 2

Percent

VCT EXH DIF1

Exhaust B Camshaft Desired Minus Actual Bank 1

Degrees

VCT EXH DIF2

Exhaust B Camshaft Desired Minus Actual Bank 2

Degrees

VCT EXH DSD

VCT Exhaust Angle Desired

Degrees

VCT EXH DSD1

VCT Exhaust Angle Desired Bank 1

Degrees

(Continued)

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Diagnostic Methods

2-21

Parameter Identification (PID)

PID

Description

Ford Units

VCT INT ACT1

Actual Intake A Camshaft Position Bank 1

Degrees

VCT INT ACT2

Actual Intake A Camshaft Position Bank 2

Degrees

VCT INT DC1

Intake A Camshaft Position Duty Cycle Bank 1

Percent

VCT INT DC2

Intake A Camshaft Position Duty Cycle Bank 2

Percent

VCT INT DIF1

Intake A Camshaft Desired Minus Actual Bank 1

Degrees

VCT INT DIF2

Intake A Camshaft Desired Minus Actual Bank 2

Degrees

VCT INTK DSD

VCT Intake Angle Desired

Degrees

VCT INTK DSD1

VCT Intake Angle Desired Bank 1

VCTSYS

Variable Cam Timing System Status

Open/Closed

VCT1 F

Variable Cam Timing Fault

Fault/No Fault

VCT2 F

Variable Cam Timing 2 Fault

Fault/No Fault

VPWR

Vehicle Power Voltage

Volts

VREF

Vehicle Reference Voltage

Volts

VSS

Vehicle Speed

Degrees

Speed

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Diagnostic Methods

Freeze Frame Data

Description Freeze frame data allows access to emission-related values from specific generic parameter identification (PID). These values are stored when an emission-related diagnostic trouble code (DTC) is stored in continuous memory. This provides a snapshot of the conditions that were present when the DTC was stored. Once one set of freeze frame data is stored, this data remains in memory even if another emission-related DTC is stored, with the exception of misfire or fuel system DTCs. Once freeze frame data for a misfire or fuel system DTC is stored it overwrites any previous data, and freeze frame data is no longer overwritten. When a DTC associated with the freeze frame data is erased or the DTCs are cleared, new freeze frame data can be stored again. In the event of multiple emission-related DTCs in memory, always note the DTC for the freeze frame data. FREEZE FRAME DATA TABLE Acronym

Description

Measurement Units

APP

D

Accelerator Pedal Position D

%

APP

E

Accelerator Pedal Position E

%

APP

F

Accelerator Pedal Position F

%

BARO

Barometric Pressure

kPa

CATTEMP11

Catalyst Temperature Bank 1, Sensor 1

Degrees

CATTEMP21

Catalyst Temperature Bank 2, Sensor 1

Degrees

CLRDIST

Distance Since Codes Cleared

Km/mi

ECT

Engine Coolant Temperature

Degrees

EQ

RAT

Commanded Equivalence Ratio

Unit

EQ

RAT11

Lambda Value Bank 1, Sensor 1

Unit

EQ

RAT21

Lambda Value Bank 2, Sensor 1

Unit

EVAPPCT

Commanded Evaporative Purge

%

FLI

Fuel Level Input

%

FRP

Fuel Rail Pressure

kPa

FUELSYS1

Open/Closed Loop 1

OL/CL/OL DRIVE/OL FAULT/CL FAULT

FUELSYS2

Open/Closed Loop 2

OL/CL/OL DRIVE/OL FAULT/CL FAULT

IAT

Intake Air Temperature

Degrees

LFT1

Long Term Fuel Bank 1

%

LFT2

Long Term Fuel Bank 2

%

LOAD

Calculated Load Value

%

MAF

Mass Air Flow Rate

g/s

MAP

Manifold Absolute Pressure

Volts/kPa/ PSI/inHg

O2S11

Bank 1 Upstream Oxygen Sensor (11)

Volts/mA

O2S12

Bank 1 Downstream Oxygen Sensor (12)

Volts

O2S21

Bank 2 Upstream Oxygen Sensor (21)

Volts/mA

O2S22

Bank 2 Downstream Oxygen Sensor (22)

Volts

RPM

Engine RPM

RPM

(Continued)

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Diagnostic Methods

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Freeze Frame Data

FREEZE FRAME DATA TABLE Acronym

Description

Measurement Units

RUNTM

Run Time

Seconds

SFT1

Short Term Fuel Bank 1

%

SFT2

Short Term Fuel Bank 2

%

SPARKADV

Spark Advance

Degrees

TAC

Commanded Throttle Actuator

%

TP

PCT

Absolute Throttle Position

%

TP REL

Relative Throttle Position

%

VS

Vehicle Speed

km/h-mph

WARMUPS

Number of Warmups Since Code Cleared

Units

Some unique PIDs are stored in the keep alive memory (KAM) of the powertrain control module (PCM) to help in diagnosing the root cause of misfires. These PIDs are collectively called misfire freeze frame (MFF) data. These parameters are separate from the generic freeze frame data stored for every MIL code. They are used for misfire diagnosis only. The MFF data could be more useful for misfire diagnosis than the generic freeze frame data. It is captured at the time of the highest misfire rate, not when the DTC is stored at the end of a 200 or 1,000 revolution block (generic freeze frame data for misfire can be stored minutes after the misfire actually occurred). The MFF PIDs are supported on all vehicles, but may not be available on all scan tools because enhanced PID access may vary by scan tool manufacturer. MISFIRE FREEZE FRAME PIDs PID Name

Description

Measurement Units

MFF EGR

EGR DPFE Sensor at the time of Misfire

Volts

MFF IAT

Intake Air Temperature at the time of Misfire

Degrees

MFF INGEAR

Transmission In Gear at time of Misfire

Yes/No

MFF LOAD

Engine Load at the time of Misfire

%

MFF PNP

Park/Neutral Position at time of Misfire

Mode

MFF RNTM

Engine Running Time at the time of Misfire

Time

MFF RPM

Engine RPM at the time of Misfire

RPM

MFF RUN

Engine Running Time at time of Misfire

Time

MFF SOAK

Engine Off Soak Time at the time of Misfire

Time

MFF TCC LOCK

Torque Converter Clutch at time of Misfire

Yes/No

MFF THR ANG

Throttle Angle at time of Misfire

%

MFF TP

Throttle Position at time of Misfire

Volts

MFF TRIP

Number of Driving Cycles at the time of Misfire (at least one 1,000 rev block)

Number of Trips

MFF VSS

Vehicle Speed at the time of Misfire

km/h-mph

MP

Learned Misfire Correction Profile

Yes/No

LRN

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Diagnostic Methods

Flash Electrically Erasable Programmable Read Only Memory (EEPROM) Description The EEPROM is contained in an integrated circuit internal to the powertrain control module (PCM). The EEPROM contains the vehicle strategy including calibration information specific to the vehicle, and is capable of being programmed or flashed repeatedly. As part of the calibration there is an area referred to as the vehicle identification (VID) block. The VID block is programmed when installing a new PCM as described under Programming the VID Block for a Replacement PCM. Failure to carry out this procedure may generate DTC P1635 or P1639. The VID block in an existing PCM can also be tailored to accommodate various hardware or parameter changes made to the vehicle since production. Failure to carry out this procedure properly may generate DTC P1635, Tire or Axle Ratio out of Acceptable Range. An incorrect tire or axle ratio is one of the main causes for DTC P1639. This is described under Making Changes to the VID Block and also under Making Changes to the PCM Calibration. The VID block contains many items used by the strategy for a variety of functions. Some of these items include the vehicle identification number (VIN), octane adjust, fuel octane, fuel type, vehicle speed limit, tire size, axle ratio, the presence of speed control, and 4-wheel drive electronic shift-on-the-fly (ESOF) versus manual shift-on-the-fly (MSOF). Only items applicable to the vehicle hardware and supported by the VID block are displayed on the scan tool. When changing items in the VID block, the strategy places range limits on certain items such as tire and axle ratio. The number of times the VID block may be reconfigured is limited. When this limit is reached, the scan tool displays a message indicating the need to flash the PCM again to reset the VID block. For Fiesta, the body control module communicates the VIN to the PCM. When a new PCM is installed, the PCM obtains the VIN the first time the ignition is turned to the ON position. If there is a concern with the VIN not being received or being invalid, DTC P0630 is set. On selected vehicles equipped with permanent DTC reporting capabilities, neutral profile correction should be learned after a PCM replacement in order to activate the misfire monitor. This can be accomplished using the Misfire Monitor Neutral Profile Learn function on the scan tool. Programming can be carried out by a local Ford dealer or any non-Ford facility. Refer to the scan tool manufacturer’s instruction manual for details.

Neutral Profile Correction — Fiesta In order for the misfire detection system to function correctly, any mechanical inaccuracies in the crankshaft position (CKP) sensor must be learned by the PCM. Neutral profile should be relearned any time the PCM, CKP sensor or the crankshaft pulse wheel is replaced or major engine repairs have been completed. Misfire detection is active before profile learning has been completed using default thresholds. When profile has been learned the vehicle specific thresholds are then used. Neutral profile correction is learned on the road by decelerating with deceleration fuel shut off (DFSO) active. Profile correction is continuos throughout the lifetime of the vehicle, when ever the learning conditions are met adaption takes place. The neutral profile correction can only be completed using the OBD Drive Cycle. Refer to the On Board Diagnostic (OBD) Drive Cycle in this section for additional information. 2011Powertrain Control/Emissions Diagnosis, 8/2010

Diagnostic Methods

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Flash Electrically Erasable Programmable Read Only Memory (EEPROM) Neutral Profile Correction — All Others In order for the misfire detection system to function correctly, any mechanical inaccuracies in the crankshaft position (CKP) sensor must be learned by the PCM. This information is stored in non-volatile memory (NVM) in the PCM. It is not cleared when the keep alive memory (KAM) is reset. Neutral profile learning is accomplished using the scan tool any time a PCM is replaced. It should also be relearned any time the CKP sensor or the crankshaft pulse wheel is replaced or major engine repairs have been completed. To determine if the neutral profile learning has been completed, check the MP LRN parameter identification (PID) using the scan tool. The PID should read YES if the neutral profile learning has been completed. If the PID reads NO, complete the neutral profile learning prior to diagnosing any misfire DTCs.

Programming the VID Block for a Replacement PCM The VID block on a replacement PCM is blank and requires programming. There are two procedures available. The first is an automatic data transfer from the old PCM to the new PCM, the second is manual data entry into the new PCM. Automatic data transfer is carried out if the old PCM is capable of communicating. This is done by using a scan tool to retrieve data from the old PCM before removing it from the vehicle. The stored data can be downloaded to the new PCM after it has been installed. For Fiesta, the body control module communicates the vehicle identification number (VIN) to the PCM. When a new PCM is installed, the PCM obtains the VIN the first time the ignition is turned to the ON position. If there is a concern with the VIN not being received or being invalid, DTC P0630 is set. Carry out manual data entry if the old PCM is damaged or incapable of communicating. Remove and install a new PCM. Using a compatible scan tool, select and carry out the module/parameter programming, referring to the scan tool manufacturer’s instruction manual. Make certain that all parameters are included. Failure to properly program tire size in revolutions per mile, (rev/mile equals 63,360 divided by the tire circumference in inches), axle ratio, 4x4 or 4x2, or MSOF and ESOF may result in DTCs P1635 and P1639. You may be instructed to contact the As-Built Data Center for the information needed to manually update the VID block with the scan tool. Contact the center only if the old PCM cannot be used or the data is corrupt. For Ford and Lincoln Mercury technicians, contact your National Hotline or the Professional Technician Society (PTS) web site for As-Built data listed under the Service Publications Index. Non-Ford technicians use the Motorcraft web site at www.motorcraft.com. From the Motorcraft home page, use the search function to find the Module Programming or As-Built Data. For Ford and Lincoln Mercury technicians, check the Programmable Module Installation link on the PTS web site for quick Programmable Module data information by vehicle.

Making Changes to the VID Block A programmed PCM may require changes to be made to certain VID information to accommodate the vehicle hardware. Refer to Module Reprogramming on the scan tool. 2011Powertrain Control/Emissions Diagnosis, 8/2010

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Diagnostic Methods

Flash Electrically Erasable Programmable Read Only Memory (EEPROM) Making Changes to the PCM Calibration At certain times, the EEPROM needs to be completely reprogrammed. This is due to changes made to the strategy or calibration after production or the need to reset the VID block because it has reached its limit. Refer to PCM or Module Reprogramming on the scan tool.

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Diagnostic Methods

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Diagnostic Monitoring Test Results Mode 6

Mode 6 allows access to the results of on board diagnostic (OBD) monitor diagnostic test results. The test values are stored at the time of the particular monitor completion. Refer to mode 6 on the scan tool for test information.

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Diagnostic Methods

On Board Diagnostic (OBD) Drive Cycle

Description of On Board Diagnostic (OBD) Drive Cycle — Fiesta The following procedure is designed to execute and complete the OBD monitors. To complete a specific monitor for repair verification, follow steps 1 through 4, then continue with the step described by the appropriate monitor found under the OBD Monitor Exercised column. For the EVAP monitor to run, the ambient air temperature must be between 3.75 to 40°C (38.8 to 104°F), and the altitude below 2,438 meters (8,000 feet). The OBD drive cycle is carried out using a scan tool. Refer to the manufacturer’s instruction manual for each described function. A detailed description for clearing the DTCs is found in this section. Refer to Clear The Continuous Diagnostic Trouble Codes (DTCs) And Reset The Emission Monitors Information in The Powertrain Control Module (PCM).

Drive Cycle Recommendations

WARNING: Strict observance of posted speed limits and attention to driving conditions are mandatory when proceeding through the following drive cycles. Failure to follow these instructions may result in personal injury. 1. Most OBD monitors complete more readily using a steady foot driving style during cruise or acceleration modes. Operating the throttle in a smooth fashion minimizes the time required for monitor completion. 2. The fuel tank level should be between 1/2 and 3/4 full with 3/4 full being the most desirable. For best results, follow each of the following steps as accurately as possible: OBD Monitor Exercised Drive Cycle Preparation

Drive Cycle Procedure 1. Install the scan tool. Turn the ignition ON with the engine OFF (do not cycle the ignition). If needed, select the appropriate vehicle and engine qualifier. Clear the continuous DTCs and reset the emission monitors information in the PCM.

Purpose of Drive Cycle Procedure Resets the OBD monitor status.

2. Begin to monitor the following PIDs (if available): ECT, OUTDR TMP, EVAPDC, FLI and TP MODE. Start the vehicle without returning the ignition to the OFF position. 3. Idle the vehicle for 30 seconds. Drive at 77 to 104 km/h (48 to 65 mph) until the engine coolant temperature (ECT) is at least 76.7°C (170°F). (Continued)

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Diagnostic Methods

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On Board Diagnostic (OBD) Drive Cycle

OBD Monitor Exercised

Drive Cycle Procedure

Purpose of Drive Cycle Procedure

Prep for Monitor Entry

4. Is the ambient air temperature (AAT) between 3.75 to 40°C (38.8 to 104°F)? If not the large leak and purge flow test will not complete. It is not possible to bypass the EVAP monitor and complete the OBD Drive Cycle.

Entry condition for EVAP large leak and purge flow test.

HO2S

Cruise between 1500 and 3000 rpm for at least 5 minutes. Allow engine to idle for 5 minutes. Accelerate to 70 km/h (43.5 mph) and hold for 5 seconds at this speed. Decelerate to 40 km/h (25 mph) with closed throttle (make sure the deceleration fuel cutoff mode has been entered).

Executes the HO2S monitor.

Catalyst

Ensure HHO2S monitor has completed. Accelerate to 70 km/h (43.5 mph) and hold for 5 seconds at this speed. Decelerate to 40 km/h (25 mph) with closed throttle (make sure the deceleration fuel cutoff mode has been entered). At 40 km/h (25 mph) return to part throttle with the smallest possible throttle movement. Repeat 5 times.

Executes the catalyst monitor.

EVAP

Cruise at speed greater than 5 km/h (3.1 mph) for at least 3 minutes. Idle engine for at least 5 minutes.

Executes the EVAP Large Leak and Purge Flow Monitor if ambient air temperature is between 3.75 to 40°C (38.8 to 104°F).

Fuel Monitor

Cruise with part throttle at 1500 - 2500 rpm for 20 minutes. Allow vehicle to idle for 10 minutes. Monitor will complete quicker if a fault is present.

Executes the fuel monitor.

Note:

Executes the misfire monitor.

Misfire

The misfire monitor will run before profile correction has been learned but for more accurate measurements profile correction should be learned.

Acceleratre to 104.6 km/h (65 mph), hold steady throttle for 5 seconds, then decelerate to 64.4 km/h (40 mph) with closed throttle and no brakes (make sure the deceleration fuel cutoff mode has been entered). Repeat 3 times. Deceleration Fuel Shut Off Rear HO2S Monitor

Accelerate to 104.6 km/h (65 mph), hold steady throttle for 5 seconds, then decelerate to 64.4 km/h (40 mph) with closed throttle and no brakes (make sure the deceleration fuel cutoff mode has been entered). Repeat 5 times.

Executes the deceleration fuel shut off rear HO2S monitor.

Readiness Check

Access the On Board System Readiness (OBD monitor status) function on the scan tool. Determine whether all noncontinuous monitors have completed.

Determines if any monitor has not completed.

With the scan tool, check for pending codes. Conduct the normal repair procedures for any pending code concern.

Determines if a pending code is preventing the completion of the OBD drive cycle.

Pending Code Check (Continued)

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Diagnostic Methods

On Board Diagnostic (OBD) Drive Cycle

OBD Monitor Exercised EVAP Small Leak

Drive Cycle Procedure

Note:

Purpose of Drive Cycle Procedure Executes the small leak monitor.

Prior to checking for a small leak, the vehicle should be driven during the hottest part of the day before leaving for overnight soak. A complete PCM power down must be completed prior to starting the engine for the drive cycle preperation drive. After the ignition is turned OFF for the overnight soak the ignition must not be turned ON prior to starting the engine in the morning. When starting the vehicle after the overnight soak the engine must be started after initial ignition ON (do not cycle the ignition). The small leak test result will be available 60 seconds after engine start.

At the end of EVAP large leak and purge flow test if no fault is found check that NVLD is closed and purge is active by checking the EVAP ACTIVE and EVAP SWITCH PIDs. Turn the ignition OFF and continue to monitor the switch position PID. Wait until the PCM powers down. The NVLD switch position should remain closed until the PCM powers down. To confirm a small leak the vehicle should be left outside overnight.

Description of On Board Diagnostic (OBD) Drive Cycle — All Others The following procedure is designed to execute and complete the OBD monitors. To complete a specific monitor for repair verification, follow steps 1 through 4, then continue with the step described by the appropriate monitor found under the OBD Monitor Exercised column. For the EVAP monitor to run, the ambient air temperature must be between 4.4 to 37.8°C (40 to 100°F), and the altitude below 2,438 meters (8,000 feet). If the OBD monitors must be completed in these conditions, the powertrain control module (PCM) must detect them once (twice on some applications) before the EVAP monitor can be bypassed and OBD monitors readied. The EVAP bypassing procedure is described in the following drive cycle. The OBD drive cycle is carried out using a scan tool. Refer to the manufacturer’s instruction manual for each described function.

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Diagnostic Methods

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On Board Diagnostic (OBD) Drive Cycle

A detailed description for clearing the DTCs is found in this section. Refer to Clear The Continuous Diagnostic Trouble Codes (DTCs) And Reset The Emission Monitors Information in The Powertrain Control Module (PCM).

Drive Cycle Recommendations

WARNING: Strict observance of posted speed limits and attention to driving conditions are mandatory when proceeding through the following drive cycles. Failure to follow these instructions may result in personal injury. 1. Most OBD monitors complete more readily using a steady foot driving style during cruise or acceleration modes. Operating the throttle in a smooth fashion minimizes the time required for monitor completion. 2. The fuel tank level should be between 1/2 and 3/4 full with 3/4 full being the most desirable. 3. The evaporative monitor can operate only during the first 30 minutes of engine operation. When executing the procedure for this monitor, stay in part throttle mode and drive in a smooth fashion to minimize fuel slosh. 4. When bypassing the EVAP engine soak times, the PCM must remain powered (key ON) after clearing the continuous DTCs and relearning emission diagnostic information. For best results, follow each of the following steps as accurately as possible: OBD Monitor Exercised Drive Cycle Preparation

Drive Cycle Procedure

Note:

To bypass the EVAP soak timer (normally 6 hours), the PCM must remain powered after clearing the continuous DTCs and resetting the emission monitors information in the PCM.

Purpose of Drive Cycle Procedure Bypasses the engine soak timer. Resets the OBD monitor status.

1. Install the scan tool. Turn the key ON with the engine OFF. Cycle the key off, then on. If needed, select the appropriate vehicle and engine qualifier. Clear the continuous DTCs and reset the emission monitors information in the PCM. 2. Begin to monitor the following PIDs (if available): ECT, EVAPDC, FLI and TP MODE. Start the vehicle without returning the key to the OFF position. (Continued)

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On Board Diagnostic (OBD) Drive Cycle

OBD Monitor Exercised

Drive Cycle Procedure

Purpose of Drive Cycle Procedure

3. Idle the vehicle for 15 seconds. Drive at 77 to 104 km/h (48 to 65 mph) until the engine coolant temperature (ECT) is at least 76.7°C (170°F). Prep for Monitor Entry

4. Is the intake air temperature (IAT) between 4.4 and 37.8°C (40 and 100°F)? If not, complete the following steps, but note that step 14 is required to bypass the EVAP monitor and complete the OBD drive cycle.

Engine warm-up and provides IAT input to the PCM.

HO2S

5. Cruise at 77 to 104 km/h (48 to 65 mph) for at least 5 minutes.

Executes the HO2S monitor.

EVAP

6. Cruise at 77 to 104 km/h (48 to 65 mph) for 10 minutes (avoid sharp turns and hills). NOTE: To initiate the monitor, the throttle should be at part throttle, EVAPDC must be greater than 75%, and FLI must be between 15 and 85%, and for fuel tanks over 25 gallons FLI must be between 30 and 85%.

Executes the EVAP monitor if the IAT is between 4.4 to 37.8°C (40 to 100°F).

Catalyst

7. Drive in stop and go traffic conditions. Include 5 different constant cruise speeds, ranging from 40 to 72 km/h (25 to 45 mph) over a 10 minute period.

Executes the catalyst monitor.

EGR

8. From a stop, idle for 30 seconds, accelerate to 72 km/h (45 mph) at 1/2 to 3/4 throttle, cruise at steady throttle for 1 minute. Repeat idle, acceleration and cruise 3 times.

Executes the EGR monitor.

CCM (Engine)

9. Bring the vehicle to a stop. Idle with the transmission in drive (neutral for M/T) for 2 minutes.

Executes the idle air control (IAC) portion of the comprehensive component monitor (CCM).

CCM (Transmission)

10. For M/T, accelerate from 0 to 80 km/h (0 to 50 mph), and continue to step 11. For A/T, from a stop and in overdrive, moderately accelerate to 80 km/h (50 mph) and cruise for at least 15 seconds. Stop the vehicle and repeat without overdrive to 64 km/h (40 mph) cruising for at least 30 seconds. While at 64 km/h (40 mph), activate the overdrive, accelerate to 80 km/h (50 mph) and cruise for at least 15 seconds. Stop for at least 20 seconds and repeat step 10 five times.

Executes the transmission portion of the CCM.

Misfire, Fuel and Deceleration Fuel Shut Off Rear HO2S Monitors

11. From a stop, accelerate to 104 km/h (65 mph), hold steady throttle for 5 seconds, then decelerate at closed throttle to 64 km/h (40 mph) (no brakes), accelerate from 64 Km/h (40 mph) to 104 Km/h (65 mph), hold steady throttle for 5 seconds, repeat deceleration 5 times.

Allows learning for the misfire monitor, and completion of the deceleration fuel shut off rear HO2S monitor.

Readiness Check

12. Access the On Board System Readiness (OBD monitor status) function on the scan tool. Determine whether all non-continuous monitors have completed. If not, go to step 13.

Determines if any monitor has not completed.

(Continued)

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On Board Diagnostic (OBD) Drive Cycle

OBD Monitor Exercised

Drive Cycle Procedure

Purpose of Drive Cycle Procedure

Pending Code Check and EVAP Monitor Bypass Check

13. With the scan tool, check for pending codes. Conduct the normal repair procedures for any pending code concern. Otherwise, repeat any incomplete monitor. If the EVAP monitor is not complete and the IAT was out of the 4.4 to 37.8°C (40 to 100°F) temperature range in step 4, or the altitude is over 2438 m (8000 ft.), the EVAP bypass procedure must be followed. Go to Step 14.

Determines if a pending code is preventing the completion of the OBD drive cycle.

EVAP Monitor Bypass

14. Park the vehicle for a minimum of 8 hours. Repeat steps 2 through 11. Do not repeat step 1.

Allows the bypass counter to increment to 2.

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Diagnostic Methods

Intermittent Diagnostic Techniques

Intermittent diagnostic techniques help find and isolate the root cause of intermittent concerns associated with the electronic engine control (EEC) system. The information is organized to help find the concern and carry out the repair. The process of finding and isolating an intermittent concern starts with recreating a fault symptom, accumulating powertrain control module (PCM) data, and comparing that data to typical values, then analyzing the results. Refer to the scan tool manufacturer’s instruction manual for the functions described below. Before proceeding, be sure that: • Customary mechanical system tests and inspections do not reveal a concern. Mechanical component conditions can make a PCM system react abnormally. • Technical Service Bulletins (TSBs) and On-line Automotive Service Information System (OASIS) messages, if available, are reviewed. • Quick Test and associated diagnostic subroutines have been completed without finding a concern, and the symptom is still present.

Recreating the Fault Recreating the concern is the first step in isolating the cause of the intermittent symptom. A thorough investigation should start with the customer information worksheet located in the back of this manual. If freeze frame data is available, it may help in recreating the conditions at the time of a malfunction indicator lamp diagnostic trouble code (MIL DTC). Listed below are some of the conditions for recreating the concern: CONDITIONS TO RECREATE FAULT Engine Type Conditions

Non-Engine Type Conditions

Engine Temperature

Ambient Temperature

Engine RPM

Moisture Conditions

Engine Load

Road Conditions (smooth-bumpy)

Engine idle/accel/deceleration

Accumulating PCM Data PCM data can be accumulated in a number of ways. This includes circuit measurements with a digital multimeter (DMM) or scan tool parameter identification (PID) data. Acquisition of PCM PID data using a scan tool is one of the easiest ways to gather information. Gather as much data as possible when the concern is occurring to prevent improper diagnosis. Data should be accumulated during different operating conditions and based on the customer description of the intermittent concern. Compare this data with the known good data values. Refer to Section 6, Typical Diagnostic Reference Values. This requires recording data in four conditions for comparison: 1) KOEO, 2) Hot Idle, 3) 48 km/h (30 mph), and 4) 89 km/h (55 mph).

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Intermittent Diagnostic Techniques

Peripheral Inputs Some signals may require certain peripherals or auxiliary tools for diagnosis. In some cases, these devices can be inserted into the measurement jacks of the scan tool or DMM. For example, connecting an electronic fuel pressure gauge to monitor and record the fuel pressure voltage reading and capturing the data would help find the fault.

Comparing PCM Data After the PCM values are acquired, it is necessary to determine the concern area. This typically requires the comparison of the actual values from the vehicle to the typical values from Section 6. Refer to Section 6, Typical Diagnostic Reference Values. The charts apply to different vehicle applications (engine, model, transmission).

Analyzing PCM Data Look for abnormal events or values that are clearly incorrect. Inspect the signals for abrupt or unexpected changes. For example, during a steady cruise most of the sensor values should be relatively stable. Sensors such as throttle position (TP) and mass air flow (MAF), as well as an RPM that changes abruptly when the vehicle is traveling at a constant speed, are clues to a possible concern area. Look for an agreement in related signals. For example, if the APP1, APP2, or APP3, changes during acceleration, a corresponding change should occur in RPM and SPARK ADV PID. Make sure the signals act in proper sequence. An increase in RPM after the TP1 and TP2 increases is expected. However, if the RPM increases without a TP1 and TP2 change, a concern may exist. Scroll through the PID data while analyzing the information. Look for sudden drops or spikes in the values.

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Diagnostic Methods

Adaptive Fuel Diagnostic Trouble Code (DTC) Diagnostic Techniques

The Adaptive Fuel DTC Diagnostic Techniques help isolate the root cause of the adaptive fuel concern. Before proceeding, attempt to verify if any driveability concerns are present. These diagnostic aids are meant as a supplement to the pinpoint test steps in Section 5. For a description of fuel trim, refer to Section 1, Powertrain Control Software, Fuel Trim. Obtain Freeze Frame Data Freeze frame data is helpful in duplicating and diagnosing adaptive fuel concerns. The data (a snapshot of certain parameter identification (PID) values recorded at the time the DTC is stored in Continuous Memory) is helpful to determine how the vehicle was being driven when the concern occurred, and is especially useful on intermittent concerns. Freeze frame data, in many cases, helps isolate possible areas of concern as well as rule out others. Refer to Freeze Frame Data in this section for a more detailed description of this data. Using the LONGFT1 and LONGFT2 (Dual Bank Engines) PIDs The LONGFT1 and LONGFT2 PIDs are useful for diagnosing fuel trim concerns. A negative PID value indicates fuel is being reduced to compensate for a rich condition. A positive PID value indicates fuel is being increased to compensate for a lean condition. It is important to know there is a separate LONGFT value used for each RPM and load point of engine operation. When viewing the LONGFT1 and LONGFT2 PIDs, the values may change a great deal as the engine is operating at different RPM and load points. This is because the fuel system may have learned corrections for fuel delivery concerns that can change as a function of engine RPM and load. The LONGFT1 and LONGFT2 PIDs display the fuel trim currently being used at that RPM and load point. Observing the changes in LONGFT1 and LONGFT2 can help when diagnosing fuel system concerns. For example: • A contaminated mass air flow (MAF) sensor results in matching LONGFT1 and LONGFT2 correction values that are negative at idle (reducing fuel), but positive (adding fuel) at higher RPM and loads. • LONGFT1 values that differ greatly from LONGFT2 values rule out concerns that are common for both banks (for example, fuel pressure concerns, MAF sensor, etc. can be ruled out). • Vacuum leaks result in large rich corrections (positive LONGFT1 and LONGFT2 values) at idle, but little or no correction at higher RPM and loads. • A plugged fuel filter results in no correction at idle, but large rich corrections (positive LONGFT1 and LONGFT2 values) at high RPM and load. Resetting Long Term Fuel Trims Long term fuel trim corrections are reset by resetting the keep alive memory (KAM). Refer to Resetting The Keep Alive Memory (KAM) in this section. After making a fuel system repair, reset the KAM. For example, if dirty or plugged injectors cause the engine to run lean and generate rich long term corrections, installing new injectors and not resetting the KAM causes the engine to run very rich. The rich correction eventually leans out during closed loop operation, but the vehicle may have poor driveability and high carbon monoxide (CO) emissions while it is learning.

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Adaptive Fuel Diagnostic Trouble Code (DTC) Diagnostic Techniques DTCs P0171 and P0174 System Too Lean Diagnostic Aids Note: If the system is lean at certain conditions, then the LONGFT PID would be a positive value at those conditions, indicating that increased fuel is needed. The ability to identify the type of lean condition causing the concern is crucial to a correct diagnosis. Air Measurement System With this condition, the engine runs rich or lean of stoichiometry (14.7:1 air/fuel ratio) if the powertrain control module (PCM) is not able to compensate enough to correct for the condition. One possibility is the mass of air entering the engine is actually greater than what the MAF sensor is indicating to the PCM. For example, with a contaminated MAF sensor, the engine runs lean at higher RPM because the PCM delivers fuel for less air than is actually entering the engine. Example: • The MAF sensor measurement is inaccurate due to a corroded connector, contaminated or dirty connector. A contaminated MAF sensor typically results in a rich system at low airflows (PCM reduces fuel) and a lean system at high airflows (PCM increases fuel). Vacuum Leaks and Unmetered Air With this condition, the engine may actually run lean of stoichiometry (14.7:1 air/fuel ratio) if the PCM is not able to compensate enough to correct for the condition. This condition can be caused by unmetered air entering the engine, or due to a MAF concern. In this situation, the volume of air entering the engine is actually greater than what the MAF sensor is indicating to the PCM. Vacuum leaks normally are most apparent when high manifold vacuum is present (for example, during idle or light throttle). If freeze frame data indicates the fault occurred at idle, a check for vacuum leaks and unmetered air might be the best starting point. For example, loose, leaking or disconnected vacuum lines, intake manifold gaskets or O-rings, throttle body gaskets, brake booster, air inlet tube, a stuck, frozen or aftermarket positive crankcase ventilation (PCV) valve, and unseated engine oil dipstick. Insufficient Fueling With this condition, the engine runs lean of stoichiometry (14.7:1 air/fuel ratio) if the PCM is not able to compensate enough to correct for the condition. This condition is caused by a fuel delivery system concern that restricts or limits the amount of fuel being delivered to the engine. This condition is normally apparent as the engine is under a heavy load and at high RPM, when a higher volume of fuel is required. If the freeze frame data indicates the concern occurs under a heavy load and at higher RPM, a check of the fuel delivery system (checking fuel pressure with engine under a load) is the best starting point. Examples of this include: • low fuel pressure (fuel pump, fuel filter, fuel leaks, restricted fuel supply lines) • fuel injector concerns Exhaust System Leaks 2011Powertrain Control/Emissions Diagnosis, 8/2010

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Adaptive Fuel Diagnostic Trouble Code (DTC) Diagnostic Techniques In this type of condition, the engine runs rich of stoichiometry (14.7:1 air/fuel ratio) because the fuel control system is adding fuel to compensate for a perceived (not actual) lean condition. This condition is caused by the heated oxygen sensor (HO2S) sensing the oxygen (air) entering the exhaust system from an external source. The PCM reacts to this exhaust leak by increasing fuel delivery. This condition causes the exhaust gas mixture from the cylinder to be rich. Examples of this include: • exhaust system leaks upstream or near the HO2S • cracked/leaking HO2S boss DTCs P0172 and P0175 System Too Rich Diagnostic Aids Note: If the system is rich at certain conditions, then the LONGFT PID would be a negative value at that airflow, indicating that decreased fuel is needed. System rich concerns are caused by fuel system concerns, although the MAF sensor and base engine (for example, engine oil contaminated with fuel) should also be checked. Air Measurement System With this condition, the engine runs rich or lean of stoichiometry (14.7:1 air/fuel ratio) if the PCM is not able to compensate enough to correct for the condition. One possibility, the MAF sensor measurement is inaccurate due to a corroded connector, contamination or dirt on the MAF screen or elements. A contaminated MAF sensor typically results in a rich system at low airflows (PCM reduces fuel) and a lean system at high airflows (PCM increases fuel). Fuel System With this condition, the engine runs rich of stoichiometry (14.7:1 air/fuel ratio), if the PCM is not able to compensate enough to correct for the condition. This situation causes a fuel delivery system that is delivering excessive fuel to the engine. Examples of this include: • fuel pressure regulator (mechanical returnless fuel systems) causes excessive fuel pressure (system rich at all airflows), fuel pressure is intermittent, going to pump deadhead pressure, then returning to normal after the engine is turned off and restarted. • fuel injector leaks (injector delivers extra fuel). • evaporative emission (EVAP) canister purge valve leak (if the canister is full of vapors, introduces extra fuel). • fuel rail pressure (FRP) sensor (electronic returnless fuel systems) concern causes the sensor to indicate a lower pressure than actual. The PCM commands a higher duty cycle to the fuel pump driver module (FPDM), causing high fuel pressure (system rich at all airflows). Intake Air System

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Adaptive Fuel Diagnostic Trouble Code (DTC) Diagnostic Techniques A restriction within any of the following components may be significant enough to affect the ability of the PCM adaptive fuel control. • air inlet tube • air cleaner element • air cleaner assembly • resonators • clean air tube Base Engine Engine oil contaminated with fuel can contribute to a rich-running engine.

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