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.
Is any voltage present?
Yes | No |
|---|---|
REPAIR the short circuit. Clear the PCM DTCs. REPEAT the self-test. | For DTC P0481, GO to KF23 . For all others, GO to KF13 . |
KF13 CHECK THE VOLTAGE TO THE FC2 AND FC4 RELAYS
• Ignition OFF.
• FC2 Relay connector disconnected.
• FC4 Relay connector disconnected.
• Ignition ON, engine OFF.
• Access the PCM and control the LFC (MODE) PID.
• Command the PID ON.
• Measure the voltage between:
( + ) FC2 Relay Connector, Harness Side | ( - ) |
|---|---|
VPWR | Ground |
• Access the PCM and control the HFC (MODE) PID.
• Command the PID ON.
• Measure the voltage between:
( + ) FC4 Relay Connector, Harness Side | ( - ) |
|---|---|
VPWR - Pin 1,3 | Ground |
Are the voltages greater than 10.5 V?
Yes | No |
|---|---|
GO to KF14 . | REPAIR the open circuit. Clear the PCM DTCs. REPEAT the self-test. |
KF14 CHECK THE FC2 AND FC4 RELAYS
• Carry out the Relay Component Test. Refer to Wiring Diagrams Cell 149.
Is a concern present?
Yes | No |
|---|---|
INSTALL a new FC2 or FC4 relay in question. Clear the PCM DTCs. REPEAT the self-test. | GO to KF15 . |
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.