P0627

P0627-FUEL PUMP RELAY CIRCUIT





For a complete wiring diagram Consult Diagrams/Electrical.

- When Monitored:
With the ignition on. Battery voltage greater than 10.4 volts.

- Set Condition:
An open or shorted condition is detected in the fuel pump relay control circuit. One Trip Fault. Three good trips to turn off the MIL.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Initial Inspection and Diagnostic Overview.

Diagnostic Test

1. ACTIVE DTC
Ignition on, engine not running.
With the scan tool, select View DTCs.
Is the DTC Active at this time?

Yes

- Go To 2

No

- Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Intermittent Condition

2. FUEL PUMP RELAY
Turn the ignition off.
Remove the Fuel Pump Relay from the IPM.
Measure the resistance of the Fuel Pump Relay Coil.
Is the resistance between 70 to 90 ohms?

Yes

- Go To 3

No

- Replace the Fuel Pump Relay.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

3. INTERNAL FUSED B+ CIRCUIT




Ignition on, engine not running.
Using a 12-volt test light connected to ground, probe the Internal Fused B+ circuit.
Does the test light illuminate brightly?

Yes

- Go To 4

No

- Repair the open or short to ground in the Internal Fused B+ circuit. Inspect the related fuse and repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

4. (F202) FUSED IGNITION SWITCH OUTPUT CIRCUIT




Ignition on, engine not running.
Using a 12-volt test light connected to ground, probe the (F202) Fused Ignition Switch Output circuit.
Does the test light illuminate brightly?

Yes

- Go To 5

No

- Repair the open or short to ground in the (F202) Fused Ignition Switch Output circuit. Inspect the related fuse and repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

5. (K31) FUEL PUMP RELAY CONTROL CIRCUIT OPEN




Turn the ignition off.
Disconnect the C3 PCM harness connector.

CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis.

Measure the resistance of the (K31) Fuel Pump Relay Control circuit from the IPM to the appropriate terminal of special tool #8815.
Is the resistance below 5.0 ohms?

Yes

- Go To 6

No

- Repair the open in the (K31) Fuel Pump Relay Control circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

6. (K31) FUEL PUMP RELAY CONTROL CIRCUIT SHORTED TO GROUND




Measure the resistance between ground and the (K31) Fuel Pump Relay Control circuit in the IPM.
Is the resistance below 100 ohms?

Yes

- Repair the short to ground in the (K31) Fuel Pump Relay Control circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Go To 7

7. POWERTRAIN CONTROL MODULE (PCM)
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Fuel Pump Module and the Powertrain Control Module.
Look for any chafed, pierced, pinched, or partially broken wires.
Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Fuel Pump Module and Powertrain Control Module connectors.
Search for any Technical Service Bulletins that may apply.
Were there any problems found?

Yes

- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Replace and program the Powertrain Control Module.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test