Where to start with these codes?

Bullyent

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P0234 over boost, P1237 fuel pump secondary circuit fault, and P0148 Fuel delivery error?.

Ive made a couple posts about this issue but my x4 finally came in and did some data logging and these codes popped up as well. not sure where to start.

60lb injectors
twin ford GT pumps
KB bap
medified fpdm
pprv delete
 

Wings65288

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Who's tuning this bad boy? My tuner helped me sift through any codes I had... I got tired of troubleshooting on my own. Most tuners are so quick and knowledgeable they can usually tell you exactly what to do. That's where I'd start personally. If you're a do it yourselfer I'll usually do this:

Not being sarcastic either:
1. Open Google
2. (Enter OBD2 code) then type SVTPerformance
3. Viola, it'll show all the threads ever made on the particular problem you're looking for on SVTPerformance
 

Bullyent

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Messages
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Who's tuning this bad boy? My tuner helped me sift through any codes I had... I got tired of troubleshooting on my own. Most tuners are so quick and knowledgeable they can usually tell you exactly what to do. That's where I'd start personally. If you're a do it yourselfer I'll usually do this:

Not being sarcastic either:
1. Open Google
2. (Enter OBD2 code) then type SVTPerformance
3. Viola, it'll show all the threads ever made on the particular problem you're looking for on SVTPerformance
I’m in contact with my tuner but very slow on replying so it’s been difficult updating him and figuring things out on my end. Yeah I’ve searched the codes and the thread made about it but different symptoms. Mine runs just has a rough idle while everyone else’s dies immediately after start or doesn’t start at all and none with this code combo. I found what each code is and what it could possibly be but I’m not sure where to start (cheapest and easiest point)
 

hotcobra03

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Code chasing does get crazy.

I use fords pin point tests.

I map out codes and most of the time with multiple codes I find they alway cross. And that’s where issue lies

I I’ve seen these codes pop on mine being stock.

I have had po234 before pop up.

It was after working on car.
The tmap sensor connector lock broke and plug wasn’t seated fully I have a zip tie now holding it
 

01yellercobra

AKA slo984now
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If you're having issues contacting your tuner it's time to find another tuner. There's no reason for a lack of communication.
 

hotcobra03

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I just looked thru pin tests

What ever you did with installation of items is most likely cause.

Fpdm.

234. In list of causes to trigger
Low

P0234 - Supercharger Overboost Condition The PCM disables (bypasses) the supercharger boost and sets a diagnostic trouble code (DTC) to keep from damaging the powertrain (engine or transmission) during potential harmful operating conditions.
  • Brake torque (brake on and throttle at wide open)

  • Transmission oil temperature (TOT) exceeds calibrated threshold

  • Engine over temperature

  • Ignition misfire exceeds calibrated threshold

  • Knock sensor (KS) failure or knock detected

  • Low speed fuel pump relay not switching
Check for other diagnostic trouble codes accompanying the P0234 or check appropriate and available PIDs related to above possible causes.

148
P0148 - Fuel Delivery Error At least one bank lean at wide open throttle.
  • Severely restricted fuel filter.

  • Severely restricted fuel supply line.

  • Damaged or contaminated mass air flow (MAF) sensor.

    1237
P1237 - Fuel Pump Secondary Circuit Malfunction
Note: For LS6/LS8 and Thunderbird, the FPDM functions are incorporated in the rear electronics module (REM). Also, the REM does not use a FPM circuit. Diagnostic information will be set through SCP.

P1237 indicates that the FPDM has detected a fuel pump secondary circuit fault. The FPDM will send a message to the PCM through the FPM circuit, indicating that this failure has been detected. The PCM will set the DTC when the message is received.
  • Open or shorted FP PWR circuit

  • Open FP RTN circuit to FPDM

  • Open or shorted circuit in the fuel pump

  • Locked fuel pump rotor

  • Damaged FPDM

  • For LS6/LS8 and Thunderbird, circuits associated with the Fuel Pump relay

  • The FPDM sends a 75% duty cycle (750 msec ON, 250 msec OFF) through the FPM circuit to the PCM while the fault is being detected by the FPDM. If the fault is no longer detected, the PCM will return to sending an "all OK" (50% duty cycle) message to the PCM. The PCM will keep P1237 stored in Continuous Memory.

  • The FPDM controls pump speed by supplying a "variable" ground on the RTN circuit.

 

hotcobra03

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234 see kj1
Listen
KJ: Supercharge Bypass Control

2003 PCED On Board Diagnostics


SECTION 5: Pinpoint Tests



Procedure revision date: 08/19/2002


KJ: Supercharge Bypass Control

← KJ: Introduction
KJ1 DTC P0234: CHECK FOR OTHER DTCS
  • Check that the engine has not been subjected to brake torquecausing the P0234.

  • Drive the vehicle for 10 to 15 minutes with the engine exceeding2,000 rpm and the engine temperature stabilizing.

  • No Starts:

  • GO to A1.

  • For Stalls:

  • Return to Symptom Charts, Symptom Charts.

  • Return to repair area and check that upper radiator hose is hotand pressurized.

  • Rerun Quick Test and retrieve KOER and continuous and retrieveDTCs.
Are any other KOEO, KOER and Continuous Memory DTCs presentwith the KOER or Continuous Memory P0234?


Yes No
KEY OFF. GO to Section 4, Powertrain Diagnostic Trouble Code (DTC) Charts, for Pinpoint Test directionand REPAIR DTCs. GO to KJ2.
KJ2 CHECK SCAN TOOL PIDS FOR CAUSES OF OVERBOOST CONDITION
  • Key on, engine running.

  • Access IAT2, TFT (5.4L SC only) and RPM PIDs.

  • Observe the PIDs for values exceeding the following limits:

  • Intake air temperature (downstream), IAT2 PID greater than 230°F.

  • Transmission fluid temperature, TFT PID greater than 275°F (5.4LSC only).
Do any of the above PIDs exceed the limit?


Yes No
For IAT2:

CHECK for low fluid level in Intercooler System. CHECK for cracked intercoolerlines. REPAIR as necessary.

For TFT (5.4L only):

CHECK for low transmission fluid level. REFER to Automatic TransmissionSection 307 in the Workshop Manual for fluid changes. GO to KJ3.
KJ3 CHECK FOR LOW SPEED FUEL PUMP RELAY NOT SWITCHING
  • Key on, engine running.

  • Access LFPF PID.
Is a fault indicated on the low speed fuel pump (FP) output?


Yes No
KEY OFF. GO to Section 4, Powertrain Diagnostic Trouble Code (DTC) Charts for diagnostic directionfollowing DTC P1232. CHECK for indications of engine knock while driving the vehicle.REPAIR as necessary. If OK, indicate to vehicle owner that transmission damagewill occur upon brake torque (reference: GO to KJ1). Otherwise,unable to determine cause of overboost condition at this time.
KJ6 DTC P0243: CHECK SUPERCHARGER (BOOST) BYPASS SOLENOIDOUTPUT
  • Key off.

  • Disconnect supercharger (boost) bypass (SCB) solenoid.

  • Connect a non-powered test lamp between SCB and VPWR circuitsat the SCB solenoid harness connector.

  • Key on, engine off.

  • Attempt to close and open SCB solenoid driver in PCM by accessingOutput Test Mode or scan tool.

  • While observing the test lamp, command the PCM outputs on andoff.
Does the test lamp cycle on and off (light up and turn off)?


Yes No
KEY OFF. GO to KJ7.
For test lamp always off:

GO to KJ8.

For test lamp always on:

KEY OFF. GO to KJ11.
KJ7 CHECK SCB SOLENOID RESISTANCE
  • Measure SCB solenoid resistance.
Is resistance between 68 and 78 ohms?


Yes No
CHECK for damaged vacuum hoses between engine intake manifoldand SCB solenoid. CHECK for vacuum reservoir assembly leaks. REPAIR or REPLACEas necessary. If OK, GO to Z1 for intermittent diagnosis. REPLACE damaged SCB solenoid.
KJ8 CHECK FOR OPEN VPWR CIRCUIT BETWEEN SCB SOLENOIDAND POWER RELAY
  • Measure voltage between VPWR circuit at the SCB solenoid harnessconnector and battery negative post.
Is voltage greater than 10.5 volts?


Yes No
KEY OFF. GO to KJ10. KEY OFF. GO to KJ9
KJ9 CHECK VPWR CIRCUIT FOR OPEN IN HARNESS
  • Disconnect PCM.

  • Measure resistance of VPWR circuit between PCM harness connectorpin and SCB solenoid harness connector.
Is resistance less than 5.0 ohms?


Yes No
GO to KJ10. REPAIR open circuit.
KJ10 CHECK SCB CIRCUIT FOR OPEN IN HARNESS
  • Measure resistance of SCB circuit between PCM harness connectorpin and SCB solenoid harness connector.
Is resistance less than 5.0 ohms?


Yes No
REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM)). REPAIR open circuit.
KJ11 CHECK SCB CIRCUIT FOR SHORT TO PWR GND IN HARNESS
  • Disconnect PCM.

  • Disconnect scan tool from DLC.

  • Measure resistance between SCB circuit and multiple PWR GND circuitsat the PCM harness connector.
Are all resistances greater than 10,000 ohms?


Yes No
RECONNECT scan tool. GO to KJ12. REPAIR short circuit.
KJ12 CHECK SCB CIRCUIT FOR SHORT TO PWR OR CHASSIS GNDIN HARNESS
  • Key on, engine off.

  • Measure voltage between SCB circuit at the PCM harness connectorand chassis ground.
Is voltage less than 1.0 volts?


Yes No
KEY OFF. REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM)). KEY OFF. REPAIR short circuit to VPWR, VREF or chassis ground.
KJ13 LACK OF POWER (LOW BOOST) - CHECK VACUUM HOSES
  • Check for holes or cracks in the vacuum hose/tube between thesupercharger bypass actuator and the supercharger bypass solenoid.

  • Check for holes or cracks in the vacuum hose/tube between thesupercharger bypass solenoid and vacuum reservoir assembly.

  • Check for bends or kinks in the vacuum hose/tube between thesupercharger bypass actuator and the supercharger bypass solenoid.

  • Check for bends or kinks in the vacuum hose/tube between thesupercharger bypass solenoid and vacuum reservoir assembly.

  • Check for disconnect hose(s) between the supercharger bypassactuator, supercharger bypass solenoid and vacuum reservior assembly.
Are any leaks (holes or cracks) or restrictions (bends orkinks) in the vacuum hose(s) present?


Yes No
REPAIR or REPLACE vacuum hose(s)/tube as necessary. RETURN to Symptom Charts, Symptom Chart 8 for Lack/Lossof Power.
  • Intro


Po148 see hc1

Listen
HC: Fuel Delivery System

2003 PCED On Board Diagnostics


SECTION 5: Pinpoint Tests



Procedure revision date: 08/10/2006


HC: Fuel Delivery System

← HC: Introduction
HC1 CHECK THE SYSTEM INTEGRITY
  • Visually inspect the complete fuel delivery system for damage and leakage.

  • Check the following:

  • Fuel lines and connections.

  • Relays

  • Fuel tank

  • Fuel pump

  • Fuel pressure regulator

  • Fuel pulse damper

  • Fuel rail at injectors

  • Damaged connector pins

  • Electrical connectors not fully engaged

  • Verify the vehicle has followed the maintenance schedule. (Fuel filter should have been replaced within the last 48,280 km (30,000 miles)).

  • Verify the Inertia Fuel Shutoff (IFS) switch is set (button pushed in). Refer to the Owner Guide for location.

  • Verify the fuse integrity.

  • Verify the battery is fully charged.

  • Verify clean sufficient fuel.
Are any of the above concerns present?


Yes No
REPAIR as necessary. GO to HC2.
HC2 CHECK ALL SYSTEM RELATED DEVICES (SENSOR, DAMPER OR REGULATOR) FOR LEAKAGE
  • Key in OFF position.

  • FP connector connected.

  • Remove the vacuum hose on each system device connected to the fuel rail.

  • Inspect for the presence of fuel in the vacuum line of each device connected to the fuel rail.

  • Key ON, engine running.

  • Check for manifold vacuum at each system related component with a vacuum line.

  • Key in OFF position.
Are all vacuum lines for system related devices indicating no fuel present?


Yes No
GO to HC3. If the vacuum line connected to a component indicates that a fuel leak is present, INSTALL a new component.
HC3 CHECK THE FUEL PRESSURE

  • WARNING: BEFORE SERVICING OR REPLACING ANY COMPONENTS IN THE FUEL SYSTEM, REDUCE THE POSSIBILITY OF INJURY OR FIRE BY FOLLOWING THE WARNING, CAUTION, AND HANDLING DIRECTIONS AT THE BEGINNING OF THIS PINPOINT TEST.
  • Key in OFF position.

  • Relieve the fuel pressure. Refer to the Workshop Manual Section 310-00, Fuel System for the Fuel System Pressure Release procedure.

  • Mechanical fuel pressure gauge connected.

  • Key ON, engine OFF.

  • Pressurize the fuel system. Refer to the Workshop Manual Section 310-00, Fuel System for the Fuel System Pressure Release procedure.

  • FP connector connected.

  • Cycle the key several times to charge the fuel system.

  • Compare the fuel pressure reading to the Fuel System Specification Chart.
Is the fuel pressure within range?


Yes No
GO to HC6. GO to HC4.
HC4 CHECK THE VOLTAGE AT THE FUEL PUMP HARNESS CONNECTOR
  • FP connector disconnected.

  • Measure the voltage between:

    ( + ) Vehicle Battery ( - ) FP Connector, Harness Side
    Positive terminal FPGND

Is the voltage greater than 10 V?


Yes No
GO to HC5. Key in OFF position. REPAIR the open circuit.
HC5 CHECK THE VOLTAGE AT THE FUEL PUMP HARNESS CONNECTOR
  • VERIFY the Inertia Fuel Shutoff (IFS) switch is set (button pushed in). REFER to the Owner Guide for location.

  • FP connector disconnected.

  • Key ON, engine OFF.

  • Access the PCM and control the FP PID.

  • Be aware that Output Test Mode turns off the FP after a calibrated time. If this happens, command the outputs on again to continue testing.

  • Measure the voltage between:

    ( + ) FP Connector, Harness Side ( - ) Vehicle Battery
    FPPWR Negative terminal

Is the voltage greater than 10 V?


Yes No
Key in OFF position.

EXIT the Output State Control.

GO to HC6. Key in OFF position. REPAIR the open circuit.
HC6 CHECK THE FUEL PRESSURE LEAKDOWN
  • Mechanical fuel pressure gauge connected.

  • Key ON, engine OFF.

  • Access the PCM and control the FP PID.

  • Run the fuel pump to obtain maximum fuel pressure.

  • Command the fuel pump off.

  • Allow the fuel pressure to stabilize.

  • Record the stabilized reading.

  • Monitor the fuel pressure for 1 minute.
Does the fuel pressure remain within 34 kPa (5 psi) of the recorded reading (RFS, MRFS) or greater than 275 kPa (40 psi) (ERFS) after 1 minute?


Yes No
For ERFS, GO to HC13.

For MRFS, GO to HC14.

For RFS, GO to HC7.
Fuel rail pressure leakdown.

GO to HC12.
HC7 CHECK FOR A VACUUM SOURCE
  • Key ON, engine running.
Is the vacuum level at the Fuel Pressure Regulator equal to manifold vacuum?


Yes No
GO to HC8. Repair as required.
HC8 CHECK THE FUEL PRESSURE REGULATOR RESPONSE

  • WARNING: STRICT OBSERVANCE OF POSTED SPEED LIMITS AND ATTENTION TO DRIVING CONDITIONS ARE MANDATORY WHEN CARRYING OUT THE ROAD TEST. FAILURE TO FOLLOW THESE INSTRUCTIONS MAY RESULT IN PERSONAL INJURY.
  • Install the fuel pressure tester.

  • Disconnect the vacuum hose at the pressure regulator.

  • Plug the hose.

  • Drive the vehicle with heavy accelerations while observing the fuel pressure gauge reading.
Does the fuel pressure reading hold steady within 21 kPa (3 psi) during the test?


Yes No
GO to HC9. GO to HC14.
HC9 CHECK THE FUEL PRESSURE REGULATOR RESPONSE TO THE DECREASE IN MANIFOLD VACUUM
  • Install the fuel pressure tester.

  • Key ON, engine running.

  • Rapidly accelerate the engine speed to 2,500 RPM, then return to idle.
Does the fuel pressure increase during rapid acceleration?


Yes No
GO to HC10. INSTALL a new fuel pressure regulator assembly.
HC10 CHECK FOR A RESTRICTED FUEL RETURN LINE
  • Install the fuel pressure tester.

  • REMOVE the fuel return line at the fuel rail.

  • Connect the short hose from the fuel rail to a clean container of at least 1.1 liter (1.0 quart) capacity.

  • Key ON, engine OFF.

  • Access the PCM and control the FP PID.

  • Run the fuel pump to obtain maximum fuel flow.

  • Record the fuel pressure.

  • Observe if fuel is being returned to the container.
Is the fuel pressure within range?


Yes No
GO to HC11. INSTALL a new fuel pressure regulator assembly.
HC11 CHECK THE FUEL RETURN SYSTEM
  • Key in OFF position.

  • Disconnect the fuel return line at the fuel rail.

  • Disconnect the fuel return line at the fuel pump.

  • CHECK for a restricted fuel return line.

  • Apply 21 to 34 kPa (3 to 5 psi) regulated shop air to the return line pressure.
Does air flow freely through the line?


Yes No
GO to HC12. REPAIR the fuel return line.
HC12 CHECK FUEL INJECTOR FLOW AND LEAKAGE
  • Check the fuel injectors for leakage and flow rate using the injector flow tester or other method such as inspecting the intake manifold for fuel.
Are test results satisfactory?


Yes No
For ERFS, GO to HC13.

For all others, GO to HC14. INSTALL a new fuel injector as necessary.
HC13 COMPARE THE FRP PID TO THE MECHANICAL GAUGE
  • Key in OFF position.

  • Relieve the fuel pressure. Refer to the Workshop Manual Section 310-00, Fuel System for the Fuel System Pressure Release procedure.

  • Disable the fuel pump.

  • Key ON, engine OFF.

  • Monitor the mechanical gauge.

  • Access the PCM and monitor the FRP PID.

  • Compare the FRP PID value to the mechanical gauge.

  • Key in OFF position.

  • Pressurize the fuel system. Refer to the Workshop Manual Section 310-00, Fuel System for the Fuel System Pressure Release procedure.

  • Key ON, engine running.

  • Allow the fuel pressure to stabilize.

  • Key in OFF position.

  • Key ON, engine OFF.

  • Compare the FRP PID value to the mechanical gauge.
Are the FRP PID values within 34 kPa (5 psi) of the mechanical gauge readings?


Yes No
GO to HC14.
INSTALL a new FRP sensor.

REFER to the fuel system WARNING information at the beginning of this pinpoint test.
HC14 MONITOR THE FUEL PRESSURE WHILE ROAD TESTING THE VEHICLE

  • WARNING: STRICT OBSERVANCE OF POSTED SPEED LIMITS AND ATTENTION TO DRIVING CONDITIONS ARE MANDATORY WHEN CARRYING OUT THE ROAD TEST. FAILURE TO FOLLOW THESE INSTRUCTIONS MAY RESULT IN PERSONAL INJURY.
  • Key in OFF position.

  • Securely route the mechanical gauge so that the gauge is viewable while road testing the vehicle.

  • Key ON, engine running.

  • Engine at normal operating temperature.

  • Monitor the mechanical gauge.

  • From a stop, accelerate to 89 km/h (55 mph) at full throttle. Repeat this 3 times.
Is the fuel pressure always greater than 240 kPa (35 psi)?


Yes No
For symptoms without DTCs, the concern is elsewhere. RETURN to Section 3, Step 2: No DTC(s) Present Symptom Chart Index for further direction.

For all others, unable to duplicate or identify the concern at this time. GO to HC15.
HC15 CHECK THE FUEL SUPPLY LINE FOR RESTRICTION
  • Key in OFF position.

  • Disconnect the fuel supply line at the fuel rail.

  • Disconnect the fuel supply line at the fuel pump.

  • Check the fuel supply line for restriction.

  • Apply 21 to 34 kPa (3 to 5 psi) air pressure to the fuel supply line.
Does air flow freely through the line?


Yes No
INSTALL a new Fuel Filter assembly.

GO to HC16. REPAIR the cause of the restriction.
HC16 VERIFY THE REPAIR

  • WARNING: STRICT OBSERVANCE OF POSTED SPEED LIMITS AND ATTENTION TO DRIVING CONDITIONS ARE MANDATORY WHEN CARRYING OUT THE ROAD TEST. FAILURE TO FOLLOW THESE INSTRUCTIONS MAY RESULT IN PERSONAL INJURY.
  • Key ON, engine running.

  • Engine at normal operating temperature.

  • Monitor the mechanical gauge.

  • From a stop, accelerate to 89 km/h (55 mph) at full throttle. Repeat this 3 times.
Is the fuel pressure always greater than 240 kPa (35 psi)?


Yes No
The test is complete and no concerns are present. INSTALL a new FP module.
  • Intro

Ok 1237 see kb47

Your Current Vehicle: 2003 Ford Mustang



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  1. Listen
    KB: Fuel Pump Driver Module (FPDM)

    2003 PCED On Board Diagnostics


    SECTION 5: Pinpoint Tests



    Procedure revision date: 07/01/2003


    KB: Fuel Pump Driver Module (FPDM)

    ← KB: Introduction
    KB1 DTC P1233 OR P1234: IS DTC P1233 OR P1234 PRESENTIN KEY ON ENGINE OFF SELF TEST
    Is DTC P1233 or P1234 present in Key On Engine Off Self-Test?


    Yes No
    A hard fault is present. GO to KB2.
    The PCM is now receiving a signal from the FPDM. One possiblecause of the DTC P1233 or P1234 is that the IFS switch was tripped, then reset.

    If engine is now a no start:

    Disregard the DTC P1233 or P1234 at this time. RETURN to Symptom Charts and CONTINUE as directed. After servicing the no start, to diagnoseintermittent causes of the DTC P1233 or P1234, RETURN to GO to KB25.

    If engine will start:

    GO to KB25 to diagnose intermittent condition.
    KB2 DOES THE ENGINE START?
    Does the engine start?


    Yes No
    GO to KB15(to check the FPM circuit). VERIFY IFS switch is set (button depressed). If OK, GO to KB3.
    KB3 CHECK POWER AND GROUND CIRCUITS TO FPDM
    • Disconnect FPDM.

    • Key on, engine off.

    • Measure voltage between the FPDM PWR pin and ground pin at theFPDM harness connector.
    Is voltage greater than 10.5 volts?

    A0051381.gif





    Yes No
    Key off. REPLACE FPDM. GO to KB4.
    KB4 CHECK POWER TO FPDM
    • Key on, engine off.

    • Measure voltage between the FPDM PWR pin at the FPDM harnessconnector and chassis ground.
    Is voltage greater than 10.5 volts?

    AA1856A.gif





    Yes No
    REPAIR open ground circuit to FPDM.
    KEY OFF. No power to FPDM.

    For Escort, Mustang:

    GO to KB5.

    All Others:

    GO to KB8.
    KB5 CHECK B+ VOLTAGE TO CCRM PIN 11 (FPDM POWER SUPPLYRELAY)
    • Disconnect CCRM.

    • Measure B+ circuit voltage at Pin 11 of the CCRM harness connector.
    Is voltage greater than 10.5 volts?


    Yes No
    For Mustang:

    GO to KB6.

    For Escort:

    GO to KB7. VERIFY integrity of related fuse. If OK, REPAIR open B+ circuit.If fuse is damaged, CHECK B+ and FPDM PWR circuits for short to ground beforereplacing.
    KB6 CHECK GROUND CIRCUIT TO CCRM PIN 18
    • Measure resistance of ground circuit between CCRM harness connectorPin 18 and chassis ground.
    Is resistance less than 5.0 ohms?


    Yes No
    GO to KB7. SERVICE open ground circuit.
    KB7 CHECK FOR OPEN FPDM PWR CIRCUIT
    • Measure resistance of FPDM PWR circuit between CCRM harness connector(pin 5) and FPDM harness connector.
    Is resistance less than 5.0 ohms?


    Yes No
    REPLACE CCRM. The FPDM PWR circuit is open. GO to KB13 to helpisolate fault.
    KB8 CHECK B+ VOLTAGE TO FPDM POWER SUPPLY RELAY
    • Disconnect FPDM power supply relay.

    • Measure B+ circuit voltage at the FPDM power supply relay harnessconnector.
    Is voltage greater than 10.5 volts?


    Yes No
    GO to KB9. VERIFY integrity of related fuse. If OK, REPAIR open B+ circuit.If fuse is damaged, CHECK B+ and FPDM PWR circuits for short to ground beforereplacing.
    KB9 CHECK FOR GROUND TO FPDM POWER SUPPLY RELAY
    • Disconnect scan tool from DLC.

    • Measure resistance of ground circuit between FPDM power supplyrelay harness connector and battery negative post.
    Is resistance less than 5.0 ohms?


    Yes No
    GO to KB10. REPAIR open circuit.
    KB10 CHECK FOR OPEN FPDM PWR CIRCUIT
    • Measure resistance of FPDM PWR circuit between FPDM power supplyrelay harness connector and FPDM harness connector.
    Is resistance less than 5.0 ohms?


    Yes No
    RECONNECT FPDM. GO to KB11. The FPDM PWR circuit is open. GO to KB13 to helpisolate fault.
    KB11 CHECK VPWR CIRCUIT VOLTAGE (IGN START/RUN for Taurus/Sable)TO FPDM POWER SUPPLY RELAY
    • Key on, engine off.

    • Measure VPWR circuit voltage (IGN START/RUN for Taurus/Sable)at the FPDM power supply relay harness connector.
    Is voltage greater than 10.5 volts?


    Yes No
    REPLACE FPDM power supply relay. REPAIR open VPWR (or IGN START/RUN) circuit.
    KB13 ISOLATE OPEN IN FPDM PWR CIRCUIT
    • Disconnect IFS switch.

    • Measure resistance of FPDM PWR circuit between IFS switch harnessconnector and FPDM power supply relay harness connector (for Escort and Mustang,CCRM harness connector [pin 5]).

    • Measure resistance of FPDM PWR circuit between FPDM harness connectorand IFS switch harness connector.
    Are both resistances less than 5.0 ohms?


    Yes No
    VERIFY that the IFS switch is set (button depressed). If OK,REPLACE IFS switch. REPAIR open in appropriate area of FPDM PWR circuit.
    KB15 CHECK FOR OPEN FPM CIRCUIT
    • Disconnect FPDM.

    • Disconnect PCM.

    • Measure resistance of FPM circuit between PCM harness connectorand the FPDM harness connector.
    Is resistance less than 5.0 ohms?


    Yes No
    GO to KB16. REPAIR open circuit.
    KB16 CHECK FPM CIRCUIT FOR SHORT TO POWER IN HARNESS
    • Key on, engine off.

    • Measure voltage between FPM circuit at the PCM harness connectorand ground.
    Is voltage less than 1.0 volt?


    Yes No
    KEY OFF. GO to KB17. REPAIR short circuit.
    KB17 CHECK FPM CIRCUIT FOR SHORT TO GROUND IN HARNESS
    • Disconnect scan tool from DLC.

    • Measure resistance between FPM circuit at the PCM harness connectorand ground.
    Is resistance greater than 10,000 ohms?


    Yes No
    GO to KB18. REPAIR short circuit.
    KB18 CHECK FOR FPM OUTPUT FROM FPDM
    • Reconnect FPDM.

    • Key on, engine off.

    • Measure dc voltage between FPM circuit at the PCM harness connectorand ground.
    Is voltage between 0.02 and 1.0 volt dc? (It is OK for thevoltage to cycle below this range and then return to within range.)


    Yes No
    REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM)). REPLACE FPDM.
    KB25 CHECK CIRCUITS THAT MAY CAUSE AN INTERMITTENT LOSSOF POWER SUPPLY TO THE FPDM. ALSO CHECK FOR INTERMITTENT OPENS OR SHORTS ONTHE FPM CIRCUIT.
    • Key on, engine off.

    • Access FPM PID.

    • Observe FPM PID for an indication of a fault while completingthe following (look for the FPM PID to change from the 50% value, or to stopfluctuating):

    • Shake, wiggle, bend the following circuits:

    • FPDM ground.

    • FPDM PWR circuit to FPDM.

    • For Escort and Mustang, the B+ circuit to CCRM pin 11. For Mustang,also the ground circuit to CCRM Pin 18.

    • For all except Escort and Mustang, the B+ and ground circuits to FPDMpower supply relay.

    • FPM circuit between the FPDM and the PCM.

    • Lightly tap on the IFS Switch, FPDM and CCRM or FPDM power supply relayto simulate road shock.

    • Key off.
    Is a fault indicated?


    Yes No
    ISOLATE fault and REPAIR as necessary. Unable to duplicate or identify fault at this time. GO to Z1.
    KB30 DTC P1235 OR P1236: IS DTC P1235 OR P1236 PRESENTIN KEY ON ENGINE OFF OR ENGINE RUNNING SELF TEST?


    NOTE
    Note: Refer to the PCM connector pin numbers in the beginning of thispinpoint test.





    NOTE
    Note: For LS6/LS8 and Thunderbird, check if Electronic Throttle Control(ETC) DTC P2105 is present. An ETC system concern could cause a P1235/P1236,and should be diagnosed first.



    Is DTC P1235 or P1236 present in Key On Engine Off or EngineRunning Self-Test?


    Yes No
    A hard fault is present. GO to KB31 to check theFP circuit.
    DTC P1235 or P1236 is intermittent.

    For LS6/LS8 and Thunderbird:

    GO to KB42.

    All others:

    GO to KB45.
    KB31 CHECK FOR OPEN FP CIRCUIT BETWEEN PCM AND FPDM
    • Disconnect FPDM.

    • Disconnect PCM.

    • Measure resistance of FP circuit between PCM harness connectorpin and the FPDM harness connector.
    Is resistance less than 5.0 ohms?


    Yes No
    GO to KB32. REPAIR open circuit.
    KB32 CHECK FP CIRCUIT FOR SHORT TO POWER IN HARNESS
    • Key on, engine off.

    • Measure voltage between FP circuit at PCM harness connector pinand ground.
    Is voltage less than 1.0 volt?


    Yes No
    KEY OFF. GO to KB33. REPAIR short circuit.
    KB33 CHECK FP CIRCUIT FOR SHORT TO GROUND IN HARNESS
    • Disconnect scan tool from DLC.

    • Measure resistance between FP circuit at PCM harness connectorpin and ground.
    Is resistance greater than 10,000 ohms?


    Yes No
    For LS6/LS8 and Thunderbird:

    GO to KB36.

    All others:

    GO to KB34. REPAIR short circuit.
    KB34 CHECK FP CIRCUIT IN FPDM
    • Reconnect FPDM.

    • Key on, engine off.

    • Measure voltage between FP circuit at PCM harness connector pinand ground.
    Is voltage between 4.5 and 5.5 volts?


    Yes No
    REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM)). REPLACE FPDM.
    KB36 CHECK FPF PID
    • Key on, engine off.

    • Access the FP and FPF PIDs on the scan tool (the FP PID may beused in the next step).

    • While viewing the FPF PID for 20 seconds, check if the FPF PIDwill indicate YES. The FPF PID may read NO in the 20 seconds, but will changeback to YES.
    Does the FPF PID indicate YES within 20 seconds?


    Yes No
    GO to KB40. GO to KB37.
    KB37 CHECK FP PID
    Does the FP PID indicate between 70 and 80%?


    Yes No
    GO to KB38. TURN KEY OFF then back ON. Wait 5 seconds. REPEAT test step.If result is now YES, follow YES result. If result is still NO, REPLACE PCM(refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM)).
    KB38 ACCESS REM PIDS AND CHECK PWM_DC1 PID
    • Access the PWM_DC1 PID from the REM menu (the PWM_DC1PID indicates the signal sent to the REM from the PCM on the FP circuit).
    Does the PWM_DC1 PID indicate between 70 and 80%?


    Yes No
    KEY OFF. No fault indicated. Disregard DTC P1235 or P1236. RETURNto Symptom Charts where DTC was received and proceed as directed. REPLACE REM.
    KB40 CHECK REM CIRCUITRY VOLTAGE ON FP CIRCUIT AT PCM
    • Key off.

    • Disconnect PCM connector B (BODY).

    • Key on, engine off.

    • Measure voltage between pin B58 at PCM harness connector B andground.
    Is voltage greater than 8 volts?


    Yes No
    REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM)). REPLACE REM.
    KB42 CHECK FP CIRCUIT FOR INTERMITTENT CONCERNS
    • Key on, engine off.

    • Access the REM PID access menu on the scan tool.

    • Access the PWM_DC1 PID from the REM menu (the PWM_DC1PID indicates the signal sent to the REM from the PCM on the FP circuit).

    • Observe the PWM_DC1 PID for indication of a fault whilecompleting the following (the PID value will change when a fault is detected):

    • Shake, wiggle and bend the FP circuit between the PCM (Pin B58) andREM (Pin J2-19).
    Is a fault indicated?


    Yes No
    ISOLATE fault and REPAIR as necessary. KEY OFF. Unable to duplicate or identify fault at this time. GO to Z1 with the following data: PWM_DC1 PID (REM menu),FP PID (PCM menu, the FP PID is the signal the PCM is sending to the REM).
    KB45 CHECK FP CIRCUIT FOR INTERMITTENT OPENS OR SHORTS
    • Key on, engine off.

    • Access FPM PID.

    • Observe the FPM PID for an indication of a fault while completingthe following (look for the FPM PID to change from the 50% value, or to stopfluctuating):

    • Shake, wiggle, bend the FP circuit between FPDM and the PCM.

    • Lightly tap on the FPDM (to simulate road shock).
    Is a fault indicated?


    Yes No
    ISOLATE fault and REPAIR as necessary. KEY OFF. Unable to duplicate or identify fault at this time. GO to Z1.
    KB47 DTC P1237 OR P1238: IS DTC P1237 OR P1238 PRESENTIN KEY ON ENGINE OFF OR ENGINE RUNNING SELF TEST
    Is DTC P1237 or P1238 present in Key On Engine Off or KeyOn Engine Running Self-Test?


    Yes No
    A hard fault is present. GO to KB48.
    DTC P1237 or P1238 is possibly intermittent.

    For LS6/LS8 and Thunderbird:

    GO to KB67.

    All others:

    GO to KB56.
    KB48 DOES THE ENGINE START?
    Does the engine start?


    Yes No
    For LS6/LS8 and Thunderbird:

    GO to KB80.

    All others:

    DISCONNECT FPDM. GO to KB59.
    For LS6/LS8 and Thunderbird:

    GO to KB61.

    All others:

    GO to KB49 to check fuel pump secondary circuits.
    KB49 CHECK FP PWR, FP RTN AND INTERNAL FUEL PUMP CIRCUITRESISTANCE
    • Disconnect scan tool from DLC.

    • Disconnect FPDM.

    • Measure resistance between FP PWR circuit and the FP RTN circuitat the FPDM harness connector.
    Is resistance less than 10.0 ohms?


    Yes No
    GO to KB50. An open secondary circuit exists. GO to KB54 toisolate fault.
    KB50 CHECK FP RTN CIRCUIT FOR SHORT TO POWER IN HARNESS
    • Key on, engine off.

    • Measure voltage between the FP RTN circuit in harness and chassisground.
    Is voltage less than 1.0 volt?


    Yes No
    GO to KB51. REPAIR short circuit.
    KB51 CHECK FP PWR CIRCUIT FOR SHORT TO GROUND IN HARNESS
    • Disconnect fuel pump.

    • Measure resistance between the FP PWR circuit in harness andground.
    Is resistance greater than 10,000 ohms?


    Yes No
    GO to KB52. REPAIR short circuit.
    KB52 CHECK FOR VOLTAGE TO FUEL PUMP
    • Reconnect FPDM.

    • Reconnect scan tool.

    • Key on, engine off.

    • Access Output Test Mode on scan tool. (To complete this teststep without a scan tool, the fuel pump can be commanded on for one secondby cycling the key from off to on. Repeat as needed.)

    • Connect digital multimeter between the FP PWR circuit and theFP RTN circuit at the fuel pump harness connector.

    • While monitoring voltage, command outputs on (this commands thefuel pump on for about 5 seconds).
    With the fuel pump commanded on, is the voltage greater than10.0 volts?


    Yes No
    REPLACE fuel pump. VERIFY vehicle battery was at proper charge during test. VERIFYpump on command did not time-out before voltage check was made. If OK, REPLACEFPDM.
    KB54 ISOLATE OPEN CIRCUIT
    • Disconnect fuel pump.

    • Measure resistance of the FP PWR circuit between the FPDM andfuel pump harness connectors.

    • Measure resistance of the FP RTN circuit between the FPDM andfuel pump harness connectors.

    • Measure internal resistance of the fuel pump.
    Is each resistance less than 10.0 ohms?


    Yes No
    No fault is detected. VERIFY results of previous test steps. REPAIR open in appropriate circuit (if open was internal topump, REPLACE fuel pump).
    KB56 VERIFY THAT DTC P1237 OR P1238 IS INTERMITTENT
    • Key on, engine off.

    • Access FPM PID.
    Is the FPM PID 75% (or varying between 250 and 400%)?


    Yes No
    A hard fault is present. GO to KB48. DTC P1237 or P1238 is intermittent. GO to KB57.
    KB57 CHECK FUEL PUMP SECONDARY CIRCUITS FOR INTERMITTENTOPEN OR SHORT
    • Key on, engine off.

    • Access FPM PID.

    • Observe the FPM PID for an indication of a fault while completingthe following (the FPM PID will change from the normal (all OK) reading whena fault is detected):

    • Shake, wiggle, bend the FP PWR circuit and FP RTN circuit between theFPDM and the fuel pump.

    • Lightly tap the fuel pump and the FPDM to simulate road shock.
    Is a fault indicated?


    Yes No
    ISOLATE fault and REPAIR as necessary. KEY OFF. GO to KB58.
    KB58 CHECK FP PWR CIRCUIT FOR SHORT TO GROUND
    • Disconnect FPDM.

    • Connect a non-powered test lamp between the FP PWR circuit andthe FPDM PWR circuit at the FPDM harness connector.

    • Key on.

    • Observe test lamp for an indication of a fault while completingthe following (the test lamp will turn on when a fault is detected, indicatinga short to ground):

    • Shake, wiggle, bend the FP PWR circuitbetween the FPDM and the fuel pump.
    Is a fault indicated?


    Yes No
    ISOLATE fault and REPAIR as necessary. KEY OFF. Unable to duplicate or identify fault at this time.RECONNECT FPDM. GO to Z1.
    KB59 CHECK FP PWR CIRCUIT FOR SHORT TO POWER
    • FPDM disconnected.

    • Key on, engine off.

    • Measure voltage between the FP PWR circuit at the FPDM harnessconnector and chassis ground.
    Is voltage less than 1.0 volt?


    Yes No
    GO to KB60. REPAIR FP PWR circuit short to power.
    KB60 CHECK FP RTN CIRCUIT FOR SHORT TO GROUND
    • FPDM disconnected.

    • Key on.

    • Measure voltage between the FPDM PWR and FP RTN circuits at theFPDM harness connector.
    Is voltage less than 1.0 volt?


    Yes No
    REPLACE FPDM. REPAIR FP RTN circuit short to ground.
    KB61 CHECK REM/FP PWR AND GROUND CIRCUIT TO REM PINSJ1-1, J1-2
    • Disconnect REM connector J1.

    • Key on.

    • Measure voltage between pins J1-1 (REM/FP PWR) and J1-2 (GND)at the REM harness connector.
    Is voltage greater than 10.5 volts?


    Yes No
    KEY OFF. GO to KB49(The FPDM functions are incorporatedin the Rear Electronics Module (REM). In the following test steps, if directedto complete an action with the FPDM, complete the action with the REM. Referto the pin numbers in the beginning of this pinpoint test). GO to KB62.
    KB62 CHECK REM/FP PWR CIRCUIT VOLTAGE TO REM USING CHASSISGROUND AS A REFERENCE
    • Key on.

    • Measure voltage between pin J1-1 of the REM harness connectorand chassis ground.
    Is voltage greater than 10.5 volts?


    Yes No
    REPAIR open ground circuit in harness to pin J1-2 of the REM. KEY OFF. GO to KB63.
    KB63 CHECK FOR B+ TO FUEL PUMP RELAY HARNESS CONNECTOR
    • Disconnect fuel pump relay.

    • Measure B+ circuit voltage at fuel pump relay harness connector.
    Is voltage greater than 10.5 volts?


    Yes No
    GO to KB64. VERIFY condition of related fuse(s). If OK, REPAIR open circuit.If B+ fuse is damaged, CHECK for B+ short to ground or FP RTN for short topower before replacing fuse.
    KB64 CHECK FOR IGN START/RUN VOLTAGE (THROUGH IFS SWITCH)TO FUEL PUMP RELAY HARNESS CONNECTOR
    • Disconnect REM connector J3.

    • Key on.

    • Measure IGN START/RUN circuit (from IFS switch) voltage at fuelpump relay harness connector.
    Is voltage greater than 10.5 volts?


    Yes No
    KEY OFF. GO to KB65. VERIFY condition of related fuse. If fuse is damaged, CHECKfor IGN START/RUN circuit short to ground before replacing fuse. If fuse isOK, GO to KB69(to isolate open circuit).
    KB65 CHECK GROUND CIRCUIT TO FUEL PUMP RELAY
    • Measure resistance of ground circuit between the fuel pump relayharness connector and ground.
    Is resistance less than 5.0 ohms?


    Yes No
    GO to KB66. REPAIR open circuit.
    KB66 CHECK REM/FP PWR CIRCUIT CONTINUITY
    • Measure resistance of REM/FP PWR circuit between the fuel pumprelay harness connector and the REM harness connector (pin J1-1).
    Is resistance less than 5.0 ohms?


    Yes No
    REPLACE fuel pump relay. REPAIR open circuit.
    KB67 CHECK REM/FP PWR, REM GROUND AND CIRCUITS ASSOCIATEDWITH THE FUEL PUMP RELAY FOR INTERMITTENTS
    • Disconnect REM connector J1.

    • Connect a non-powered test lamp between pins J1-1 (REM/FP PWR)and J1-2 (GND) of the REM harness connector.

    • Key on.

    • Observe test lamp for an indication of a fault while completingthe following (the test lamp will go out when a fault is detected):

    • Shake, wiggle and bend the REM/FP PWR and GND (pin J1-2) circuitsto REM.

    • Shake, wiggle and bend the circuits going to the fuel pump relay(IGN START/RUN, B+ ground).

    • Lightly tap the fuel pump relay and IFS switch to simulate roadshock.
    Is a fault detected?


    Yes No
    ISOLATE fault and REPAIR as necessary. KEY OFF. GO to KB68.
    KB68 CHECK FP PWR AND FP RTN CIRCUITS FOR INTERMITTENTCONCERNS
    • Connect a DVOM (set to measure resistance) between pins J1-11(FP PWR) and J1-12 (FP RTN).

    • Observe DVOM for an indication of a fault while completing thefollowing (resistance will change suddenly [from less than 10 ohms] when afault is detected):

    • Shake, wiggle and bend the FP PWR andFP RTN circuits between the fuel pump and REM.

    • Connect DVOM between pin J1-12 (FP RTN) and ground.

    • Observe DVOM for an indication of a fault while completing thefollowing (resistance will change suddenly [from greater than 10,000 ohms]when a short to ground is detected):

    • Shake, wiggle andbend the FP PWR and FP RTN circuits between the fuel pump and REM.
    Is a fault indicated?


    Yes No
    ISOLATE fault and REPAIR as necessary. KEY OFF. Unable to duplicate or identify fault at this time.REMOVE DVOM, RECONNECT REM. GO to Z1.
    KB69 ISOLATE OPEN IN IGN START/RUN CIRCUIT
    • Disconnect Inertia Fuel Shutoff (IFS) switch.

    • Measure resistance across the normally closed contacts of theIFS switch. Note resistance.

    • Measure resistance of IGN START/RUN circuit between the IFS switchand fuel pump relay harness connectors.
    Are both resistances less than 5.0 ohms?


    Yes No
    REPAIR open IGN START/RUN circuit to IFS switch. If open was in IGN START/RUN circuit, REPAIR open. If open wasin IFS switch, REPLACE switch.
    KB70 SENT HERE FROM PINPOINT TEST HC WITH LOW VOLTAGEAT FUEL PUMP AND NO DTCs: CHECK BATTERY VOLTAGE WITH OUTPUTS COMMANDED ON
    • Scan tool connected.

    • Fuel pump disconnected.

    • Key on.

    • Connect digital multimeter to the battery positive and batterynegative posts.

    • While monitoring battery voltage, command outputs on. Note voltagewithin 5 seconds.

    • Command outputs off.
    Was battery voltage greater than 11.0 volts?


    Yes No
    GO to KB71. Battery voltage is low. REFER to Charging System, General InformationSection 414-00 in the Workshop Manual.
    KB71 CHECK GROUND CIRCUIT TO FUEL PUMP BY MEASURING VOLTAGEAT FUEL PUMP USING BATTERY NEGATIVE AS A REFERENCE
    • Connect digital multimeter between the FP PWR circuit at thefuel pump harness connector and the battery negative post.

    • Key on.

    • While monitoring voltage, command outputs on. Note voltage within5 seconds.
    Is voltage greater than 10.5 volts?


    Yes No
    Ground fault to fuel pump indicated. CHECK all associated wiringand connections for the fuel pump and FPDM ground circuits. Carefully CHECKthe FPDM ground connection to chassis ground. REPAIR as necessary. KEY OFF. Ground circuit to fuel pump is OK. GO to KB72.
    KB72 CHECK VOLTAGE TO FUEL PUMP DRIVER MODULE (FPDM)
    • Disconnect fuel pump driver module (FPDM).

    • Key on.

    • Measure voltage between the FPDM PWR circuit at the FPDM harnessconnector and the battery negative post.
    Is voltage greater than 10.5 volts?


    Yes No
    KEY OFF. GO to KB73. KEY OFF. Improper voltage is being supplied to FPDM. GO to KB75.
    KB73 CHECK FP PWR CIRCUIT
    • Connect a jumper wire between the FPDM PWR pin and FP PWR pinat the FPDM harness connector.

    • Key on.

    • Measure voltage between the FP PWR circuit at the fuel pump harnessconnector and the battery negative post.
    Is voltage greater than 10.5 volts, AND within 0.5 volt ofthe reading in KB72?

    AA0797C.gif





    Yes No
    KEY OFF. REMOVE jumper. VERIFY previous test steps. CHECK relatedconnectors for corrosion, etc. If all checks are OK, REPLACE FPDM. KEY OFF. REMOVE jumper. CHECK for causes of high resistancein FP PWR circuit.
    KB75 CHECK B+ TO FPDM POWER SUPPLY RELAY (or CCRM)
    • Disconnect CCRM (Escort, Mustang) or FPDM power supply relay(all others).

    • Key on (to put same load on battery as previous steps).

    • For Escort, Mustang:

    • Measure voltage betweenpin 11 (B+) of the CCRM harness connector and the battery negative post.

    • For all others:

    • Measure voltage between theB+ circuit at the FPDM power supply relay harness connector and the batterynegative post.
    Is voltage greater than 10.5 volts?


    Yes No
    KEY OFF. GO to KB76. Improper voltage is being supplied to the CCRM or FPDM powersupply relay. CHECK associated wiring, connectors, etc. REPAIR as necessary.
    KB76 CHECK FPDM PWR CIRCUIT
    • For Escort, Mustang:

    • Connect a jumper wirebetween pin 11 (B+) and pin 5 at the CCRM harness connector.

    • For all others:

    • Connect a jumper wire betweenthe B+ and the FPDM PWR circuit at the FPDM power supply relay harness connector.

    • Key on.

    • Measure voltage between the FPDM PWR circuit at the FPDM harnessconnector and the battery negative post.
    Is voltage greater than 10.5 volts?


    Yes No
    VERIFY previous test steps. CHECK related connectors for corrosion,etc. If all checks are OK, REPLACE FPDM. CHECK for causes of high resistance in associated connectorsand wiring of the FPDM PWR VPWR circuit, including the IFS switch and itsconnector. REPAIR as necessary.
    KB80 CHECK FP RTN CIRCUIT FOR SHORT TO GROUND
    • Disconnect REM connector J1.

    • Key on.

    • Measure voltage between pins J1-1 and J1-12 at the REM harnessconnector.
    Is voltage less than 1.0 volt?


    Yes No
    GO to KB67. REPAIR FP RTN circuit short to ground.
    KB85 COMPLETE REAR ELECTRONICS MODULE SELF-TEST TO VERIFYIFS SWITCH INPUT TO REM (REM PIN J3-8)
    • Complete Rear Electronics Module Self-Test (refer to WorkshopManual section 419-10, Multifunction Electronic Control Modules, for directions).
    Is REM DTC B2172 present?


    Yes No
    GO to KB86. GO to A1.
    KB86 B2172: CHECK IFS SWITCH INPUT CIRCUIT TO REM (REMPIN J3-8)
    • Disconnect REM connector J3.

    • Key on, engine off.

    • Measure voltage at pin J3-8 of the REM harness connector.
    Is voltage greater than 10.5 volts?


    Yes No
    KEY OFF.

    If engine is a no start and REM DTC B2172 was receivedin on-demand self-test mode:

    REPLACE REM.

    If engine will start or REM DTC B2172 is a continuousmemory DTC:

    DTC is intermittent. If engine is a no start, return to Symptom Charts tocontinue diagnosis. If engine will start, GO to Z1(even thoughPPT Z is designed for PCM intermittents, the diagnostic techniques will helpwith the REM diagnosis). KEY OFF. VERIFY IFS switch is not open. If OK, REPAIR open circuitbetween IFS switch and REM pin J3-8.
    • Intro
 

Bullyent

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@hotcobra03 sweet thanks man. im currently reading this over. also, i did some data logging and my "returnless fuel pump duty cycle" is staying at .006607 the whole time (about 2 min of idle) does that seem extremely low?
 

01yellercobra

AKA slo984now
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@hotcobra03 sweet thanks man. im currently reading this over. also, i did some data logging and my "returnless fuel pump duty cycle" is staying at .006607 the whole time (about 2 min of idle) does that seem extremely low?

You're watching the wrong PID. There's usually one in all caps and one all lower case. I would select them both and see which one shows a reading.
 

Bullyent

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You're watching the wrong PID. There's usually one in all caps and one all lower case. I would select them both and see which one shows a reading.
i used the config file that one of the tuners on here gave me. its in all caps. Ill try to run it again. can you suggest any other PIDs i should select.
Im also reading that since I have done the pprv delete, the line could have broke. dropping the tank later and checking it.
 

Bullyent

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@slo984now @hotcobra03 ok I dropped the tank. Took the fuel hat off and the fuel filter that’s attached at the bottom of the fuel pump is completely off. So 1 of the 2 GT pumps filter (tampon looking thing) is completely off and not just the mesh material part, but the circular neck that actually attaches the filter and the pump together is off. I have a video but I’m not sure how to post it on here. Safe to say that’s causing it? The pprv delete hoses are fine. Didn’t pop off or any holes.
 

01yellercobra

AKA slo984now
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Maybe the sock was tweaked and blocking the inlet. I'd do some searching and see if theres a way to check the pumps. It would suck to put it all back together with a bad pump.
 

Bullyent

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Maybe the sock was tweaked and blocking the inlet. I'd do some searching and see if theres a way to check the pumps. It would suck to put it all back together with a bad pump.
So the single hose connected to the Y of the pprv delete popped off at the hat. I’m not sure if it popped off as I was removing the hat because I did have to manipulate the hose position to get it out but I dont think it was caught anywhere to the point where it completely came off. It does have a hose clamp and it was off the hose as well. I think this is the issue. Put everything back together but it got dark and cockroaches started crawling around me. I just need to put back one bolt on the tank strap that holds the tank and connect all the wires in the truck. I’ll update once I do so but I’m fairly certain that’s what’s causing it. I think the hose inside the tank that connects to the line outside that leads to the fuel filter was barely holding on.
 

01yellercobra

AKA slo984now
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If the clamp popped off at all it was leaking fuel. It doesn't take much to leak at 40+psi. Sucks you had to drop the tank. But hopefully it's all good now.
 

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