Vehicle applicability: This diagnostic supplement covers multiple Ford vehicles and engines. Follow the application named in the source below. Some references apply to vehicles other than Mustang.
HC3 CHECK THE FUEL PUMP GROUND CIRCUIT FOR AN OPEN CIRCUIT
• Ignition OFF.
• FP connector disconnected.
• For Mustang 5.2L,
• Measure the resistance between:
( + ) FP Connector, Harness Side | ( - ) |
|---|---|
FPRTN | Ground |
FP2RTN | Ground |
• For all others,
• Measure the resistance between:
( + ) FP Connector, Harness Side | ( - ) |
|---|---|
FPRTN | Ground |
Are the resistances less than 5 ohms?
Yes | No |
|---|---|
GO to HC4 . | REPAIR the open circuit. Clear the PCM DTCs. REPEAT the self-test. |
HC4 CHECK THE FUEL PUMP POWER CIRCUIT FOR AN OPEN
Note: During output state control, the fuel pump stays commanded on for only about 5 seconds. Be aware that output state control turns the FP off after a calibrated time. If this happens, command the output ON to continue testing.
• Verify the inertia fuel shutoff (IFS) switch is set (button pushed in). Refer to the Owner's Literature, Roadside Emergencies for the location of the IFS switch (if equipped).
• Ignition ON, engine OFF.
• For Mustang 5.2L,
• Measure the voltage between:
( + ) FP Connector, Harness Side | ( - ) Vehicle Battery |
|---|---|
FPPWR | Negative terminal |
FP2PWR | Negative terminal |
• For all others,
• Measure the voltage between:
2016 Mustang workshop publication supplied to Mustang Atlas. Original technical text and illustrations; HTML formatting by Mustang Atlas. Source page numbering is retained for traceability. Follow the configuration, revision, warnings, and cross-references in the material. About this edition.