NGC

P127C-FUEL PUMP CONTROL CIRCUIT 2 LOW (TIPM)

For a complete wiring diagram Consult Diagrams/Electrical.

- When Monitored:
With the ignition on. Battery voltage greater than 10.4 volts and the 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 DTC Active at this time?

Yes

- Go to 2

No

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

2. FUEL PUMP MODULE
Turn the ignition off.
Disconnect the Fuel Pump Module harness connector.
Ignition on, engine not running.
Using the scan tool under the TIPM Actuators, actuate 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.

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

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

Yes

- Replace the Fuel Pump Module.
- Perform the PCM Verification Test. Powertrain Verification Test

No

- Go to 3

3. (N1) FUEL PUMP CONTROL OUTPUT CIRCUIT SHORTED TO GROUND
Turn the ignition off
Disconnect the TIPM C7 harness connector.
Measure the resistance between ground and the (N1) Fuel Pump Control Output circuit at the TIPM C7 harness connector.
Is the resistance below 100 ohms?

Yes

- Repair the short to ground in the (N1) Fuel Pump Control Output circuit.
- Perform the PCM Verification Test. Powertrain Verification Test

No

- Go to 4

4. 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 PCM Verification Test. Powertrain Verification Test

No

- Replace the Totally Integrated Power Module.
- Perform the PCM Verification Test. Powertrain Verification Test