P127D

P127D-FUEL PUMP CONTROL CIRCUIT 2 HIGH





For a complete wiring diagram, refer to the Wiring Information.

- When Monitored:
With the ignition on.

The battery voltage greater than 10.4 volts and the Main Relay on.

Totally Integrated Power Module (TIPM) requesting Fuel Pump operation.

- Set Condition:
Actual Fuel Pump state is not equal to the desired state. One Trip Fault. Three good trips to turn off the MIL.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.

1. DTC IS ACTIVE

NOTE: If P0627, P0628 or P0629 has set along with this DTC, diagnose those DTCs first before continuing.

1. Ignition on, engine not running.
2. With the scan tool, select View DTCs.

Is the status Active for this DTC?

Yes

- Go To 2

No

- Perform the CHECKING FOR AN INTERMITTENT DTC diagnostic procedure. Intermittent Condition Test.

2. (N1) FUEL PUMP CONTROL OUTPUT CIRCUIT SHORTED TO BATTERY VOLTAGE




1. Turn the ignition off.
2. Disconnect the TIPM C7 harness connector.
3. Turn the ignition on.
4. Measure the voltage between ground and the (N1) Fuel Pump Control Output circuit in the TIPM C7 harness connector.

Is there any voltage present?

Yes

- Repair the short to battery voltage in the (N1) Fuel Pump Control Output circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 3

3. (Z906) FUEL PUMP MOTOR GROUND CIRCUIT




1. Turn the ignition off.
2. Disconnect the Fuel Pump Module harness connector.
3. Using a 12-volt test light to 12-volts, check the (Z906) Fuel Pump Motor Ground circuit in the Fuel Pump Module harness connector.

NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.

Does the test light illuminate brightly?

Yes

- Go To 4

No

- Repair the (Z906) Fuel Pump Motor Ground circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

4. FUEL PUMP MODULE




1. Connect the TIPM C7 harness connectors.
2. Ignition on, engine not running.
3. With the scan tool, actuate the Fuel Pump.
4. Using a 12-volt test light connected to ground, check the (N1) Fuel Pump Control Output circuit at the Fuel Pump Module harness connector.

Does the test light illuminate brightly and flash on and off?

Yes

- Replace the Fuel Pump Module.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 5

5. TOTALLY INTEGRATED POWER MODULE

NOTE: Before continuing, check the TIPM harness connector terminals for corrosion, damage or terminal push out. Repair as necessary.

1. Using the schematics as a guide, inspect the wire harness and connectors.
2. Pay particular attention to all Power and Ground circuits.

Were any problems found?

Yes

- Repair as necessary.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Replace the Totally Integrated Power Module.
- Perform the BODY VERIFICATION TEST. Body Verification Test.