getting code p0231 sounds electrical . ford wants to replace high pressure pump for 4300$ they also just did all the rockers so maybe they chaffed a wire and are lying to us.. also a question about replacing inertia switch i read was a problem on one persons truck doing p0231 ? any ideals

also truck was doing 65 on hwy and just died as if out of fuel. truck will not fire with WD 40. i was told not to use starter fluid but if it does not kick its electrical

 

P0231 Fuel Pump Secondary Circuit Low....did you check the fuses?

 

Yeah checked them all.

 

don't use starter fluid/either or wd40..anything. If it were to fire then you might have a runaway on your hands.

Don't ever do something like that with a truck with glowplugs and a turbo.

 

Where in Texas are you located?

 

P0231 refers to the low pressure fuel pump, the one in the HFCM on the frame rail, not the high pressure fuel pump. If they are misdiagnosing this that badly I'd get my truck out of there ASAP.

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P0231 - Fuel Pump Secondary Circuit Low
Description: The powertrain control module (PCM) monitors the fuel pump monitor (FPM) circuit. The test fails if the PCM commands the fuel pump ON and B+ voltage is not detected on the FPM circuit.
Possible Causes: Inertia fuel shutoff (IFS) switch
Fuel pump relay
FP circuit open in the harness
FP circuit short to voltage in the harness

Diagnostic Aids: Disregard a secondary fuel pump circuit DTC P0231 at this time and diagnose fuel pump control circuit DTCs P0627 or P0629 (if present). DTC P0231 may be set as the result of the FP circuit concern.
Application Key On Engine Off Key On Engine Running Continuous Memory
All GO to Pinpoint Test MA .

MA: Fuel Pump Control - Low Pressure Pump MA: Introduction
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MA1 PRELIMINARY DIAGNOSIS FOR DIAGNOSTIC TROUBLE CODES (DTCS) P0231, P0232, P0627, P0628 OR P0629
Retrieve and record all DTCs.
Access the freeze frame data (if available) and record the DTC conditions.
Clear the DTCs.
Carry out the KOEO and KOER self-test.
Are any DTCs present?
Yes No
For DTCs P0627, P0628 and P0629, GO to MA2 .
For DTC P0231, GO to MA7 .
For DTC P0232, GO to MA13 . GO to MA2 .

MA2 CHECK VPWR AT THE FUEL PUMP RELAY
Key in OFF position.
FP Relay connector disconnected.
Key ON, engine OFF.
Measure the voltage between:
( + ) FP Relay Connector, Harness Side ( - )
VPWR - Pin 86 Ground

Is the voltage greater than 10 V?
Yes No
GO to MA3 . REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.

MA3 CHECK THE FUEL PUMP RELAY
Carry out the fuel pump relay component test. Refer to the Wiring Diagrams Cell 149 Component Testing.
Is a concern present?
Yes No
INSTALL a new FP relay. CLEAR the DTCs. REPEAT the self-test. GO to MA4 .

MA4 CHECK THE FP CIRCUIT FOR AN OPEN IN THE HARNESS
Key in OFF position.
PCM-B connector disconnected.
Measure the resistance between:
( + ) FP Relay Connector, Harness Side ( - ) PCM-B Connector, Harness Side
FP - Pin 85 FP - Pin 56

Is the resistance less than 5 ohms?
Yes No
GO to MA5 . REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.

MA5 CHECK THE FP CIRCUIT FOR A SHORT TO VOLTAGE IN THE HARNESS
Key ON, engine OFF.
Measure the voltage between:
( + ) PCM-B Connector, Harness Side ( - )
FP - Pin 56 Ground

Is any voltage present?
Yes No
REPAIR the short circuit. CLEAR the DTCs. REPEAT the self-test. GO to MA6 .

MA6 CHECK THE FP CIRCUIT FOR A SHORT TO GROUND IN THE HARNESS
Key in OFF position.
Measure the resistance between:
( + ) PCM-B Connector, Harness Side ( - )
FP - Pin 56 Ground

Is the resistance greater than 10K ohms?
Yes No
GO to MA19 . REPAIR the short circuit. CLEAR the DTCs. REPEAT the self-test.

MA7 DTC P0231: CHECK THE INTERNAL RESISTANCE OF THE IFS SWITCH
Note: DTC P0231 may be set as a result of a FP circuit concern. Disregard a secondary fuel pump circuit DTC P0231 at this time and diagnose fuel pump control circuit DTCs P0627 or P0629 (if present).
Note: Verify the inertia fuel shutoff (IFS) switch is set (button pushed in). Refer to the Owner's Literature for location.
Key in OFF position.
IFS Switch connector disconnected.
Measure the resistance between:
( + ) IFS Switch Connector, Component Side ( - ) IFS Switch Connector, Component Side
B+ - Pin 2 IS - Pin 1

Is the resistance less than 5 ohms?
Yes No
GO to MA8 . INSTALL a new IFS switch. REFER to the Workshop Manual Section 301-01, Fuel Tank And Lines.
CLEAR the DTCs. REPEAT the self-test.

MA8 CHECK THE FUEL PUMP VOLTAGE
Key ON, engine OFF.
Measure the voltage between:
( + ) IFS Switch Connector, Harness Side ( - )
B+ - Pin 2 Ground

Is the voltage greater than 10 V for approximately 30 seconds?
Yes No
GO to MA12 . GO to MA9 .

MA9 CHECK THE FUEL PUMP VOLTAGE CIRCUIT FOR AN OPEN
Key in OFF position.
FP Relay connector disconnected.
Measure the resistance between:
( + ) IFS Switch Connector, Harness Side ( - ) FP Relay Connector, Harness Side
B+ - Pin 2 FPPWR - Pin 87

Is the resistance less than 5 ohms?
Yes No
GO to MA10 . REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.

MA10 CHECK VPWR AT THE FUEL PUMP RELAY
Key ON, engine OFF.
Measure the voltage between:
( + ) FP Relay Connector, Harness Side ( - )
VPWR - Pin 86 Ground
B+ - Pin 30 Ground

Are the voltages greater than 10 V?
Yes No
GO to MA11 . REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.

MA11 CHECK THE FUEL PUMP RELAY
Carry out the fuel pump relay component test. Refer to the Wiring Diagrams Cell 149 Component Testing.
Is a concern present?
Yes No
INSTALL a new FP relay. CLEAR the DTCs. REPEAT the self-test. GO to MA12 .

MA12 CHECK THE FP CIRCUIT FOR AN OPEN IN THE HARNESS
Key in OFF position.
PCM-B connector disconnected.
Measure the resistance between:
( + ) PCM-B Connector, Harness Side ( - ) FP Relay Connector, Harness Side
FP - Pin 56 FP - Pin 85

Is the resistance less than 5 ohms?
Yes No
GO to MA19 . REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.

MA13 DTC P0232: CHECK THE FUEL PUMP
Note: DTC P0232 may be set as a result of a FP circuit concern. Disregard a secondary fuel pump circuit DTC P0232 at this time and diagnose fuel pump control circuit DTC P0628 (if present).
Key in OFF position.
FP Relay connector disconnected.
Key ON, engine OFF.
Is the fuel pump on?
Yes No
GO to MA14 . GO to MA15 .

MA14 CHECK THE FPM CIRCUIT FOR A SHORT TO VOLTAGE IN THE HARNESS
Key in OFF position.
PCM-B connector disconnected.
FP connector disconnected.
Key ON, engine OFF.
Measure the voltage between:
( + ) PCM-B Connector, Harness Side ( - )
FPM - Pin 15 Ground

Is any voltage present?
Yes No
REPAIR the short circuit. CLEAR the DTCs. REPEAT the self-test. GO to MA19 .

MA15 CHECK THE FPM CIRCUIT FOR AN OPEN IN THE HARNESS
Key in OFF position.
PCM-B connector disconnected.
FP connector disconnected.
Measure the resistance between:
( + ) PCM-B Connector, Harness Side ( - ) FP Connector, Harness Side
FPM - Pin 15 FPPWR - Pin 1

Is the resistance less than 5 ohms?
Yes No
GO to MA16 . REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.

MA16 CHECK THE FUEL PUMP GROUND FOR AN OPEN IN HARNESS
Measure the resistance between:
( + ) FP Connector, Harness Side ( - )
FPGND - Pin 2 Ground

Is the resistance less than 5 ohms?
Yes No
GO to MA17 . REPAIR the open circuit. CLEAR the DTCs. REPEAT the self-test.

MA17 CHECK THE FUEL PUMP RESISTANCE
Measure the resistance between:
( + ) FP Connector, Component Side ( - ) FP Connector, Component Side
FPPWR - Pin 1 FPGND - Pin 2

Is the resistance less than 5 ohms?
Yes No
GO to MA18 . INSTALL a new FP. REFER to the Workshop Manual Section 303-04, Fuel Charging and Controls.
CLEAR the DTCs. REPEAT the self-test.

MA18 CHECK THE FUEL PUMP RELAY
Carry out the fuel pump relay component test. Refer to the Wiring Diagrams Cell 149 Component Testing.
Is a concern present?
Yes No
INSTALL a new FP relay. CLEAR the DTCs. REPEAT the self-test. GO to MA19 .

MA19 CHECK FOR CORRECT PCM OPERATION
Disconnect all the PCM connectors.
Visually inspect for:
pushed out pins
corrosion
Connect all the PCM connectors and make sure they seat correctly.
Carry out the PCM self-test and verify the concern is still present.
Is the concern still present?
Yes No
INSTALL a new PCM. REFER to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) . The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.