GPEC

P127D-FUEL PUMP CONTROL CIRCUIT 2 HIGH (TIPM)





For a complete wiring diagram Consult Diagrams/Electrical.

- When Monitored:
With the ignition on. Battery voltage greater than 10.4 volts and the ASD/Main Relay on. TIPM requesting Fuel Pump operation.

- Set Condition:
Actual Fuel Pump state is not equal to desired state. 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. DTC IS ACTIVE
NOTE: If P0627, P0628 or P0629 has set along with this DTC, diagnose those DTC(s) first before continuing.

Ignition on, engine not running.
With the scan tool, select View DTCs.
Is the status Active for this DTC?

Yes

- Go to 2

No

- Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure.Checking For An Intermittent DTC

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




Turn the ignition off
Disconnect the C7 TIPM harness connector.
Turn the ignition on.
Using a voltmeter, measure the voltage of the (N1) Fuel Pump Control Output circuit in the C7 TIPM harness connector.
Does the voltmeter indicate voltage present?

Yes

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

No

- Go to 3

3. FUEL PUMP MOTOR GROUND CIRCUIT




Turn the ignition off.
Disconnect the Fuel Pump Module harness connector.

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

Using a 12-volt test light to battery voltage, probe the 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 Fuel Pump Motor Ground circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

4. FUEL PUMP MODULE




Connect the C7 TIPM harness connectors.
Ignition on, engine not running.
Using the scan tool under the TIPM Actuators, actuate (Toggle) the Fuel Pump.
With a 12-volt test light connected to ground, probe 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 POWERTRAIN VERIFICATION TEST. Powertrain 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.

Using the schematics as a guide, inspect the wire harness and connectors.
Pay particular attention to all Power and Ground circuits.
Were any problems found?

Yes

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

No

- Replace the Totally Integrated Power Module.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test