P0628

P0628-FUEL PUMP CONTROL CIRCUIT LOW







- When Monitored:
With the engine running and battery voltage greater than 10.4 volts.

- Set Condition:
The Powertrain Control Module (PCM) detects that the fuel pump control is shorted low.





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

1. DTC IS ACTIVE
1. Attempt to start the engine. If the engine will not start, crank the engine for five seconds.

WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury.

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. Checking for an Intermittent DTC.

2. (K31) FUEL PUMP CONTROL CIRCUIT SHORTED TO GROUND




1. Turn the ignition off.
2. Disconnect the Totally Integrated Power Module (TIPM) C2 harness connector.
3. Disconnect the Powertrain Control Module (PCM) harness connector.
4. Measure the resistance between ground and the (K31) Fuel Pump Control circuit in the Totally Integrated Power Module (TIPM) harness connector.

Is the resistance below 100 Ohms?

Yes

- Repair the (K31) Fuel Pump Control circuit for a short to ground.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

No

- Go To 3

3. (K31) FUEL PUMP CONTROL CIRCUIT OPEN OR HIGH RESISTANCE





NOTE: When checking circuits at the Powertrain Control Module (PCM), be careful not to damage or distort the connector terminals. Improper measurement technique could result in poor pin to terminal contact.

1. Measure the resistance of the (K31) Fuel Pump Control circuit between the Totally Integrated Power Module (TIPM) harness connector and the Powertrain Control Module (PCM) harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Go To 4

No

- Repair the (K31) Fuel Pump Control circuit for an open circuit or high resistance.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

4. FUEL PUMP CONTROL OPEN DTC SET
1. Connect the Powertrain Control Module (PCM) connector.
2. Turn the ignition on.
3. With the scan tool, select View DTCs.

NOTE: With the TIPM connector disconnected, the PCM should display a Fuel Pump Control circuit open DTC.

Is the status Active for the Fuel Pump Control circuit open DTC?

Yes

- Go To 5

No

- Go To 6

5. TOTALLY INTEGRATED POWER MODULE (TIPM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Totally Integrated Power Module (TIPM) and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals.
4. Perform any Technical Service Bulletins that may apply.

Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

No

- Replace the Totally Integrated Power Module (TIPM).
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

6. POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Totally Integrated Power Module (TIPM) and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals.
4. Perform any Technical Service Bulletins that may apply.

Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM VERIFICATION TEST. PCM Verification Test.

No

- Replace and program the Powertrain Control Module (PCM).
- Perform the PCM VERIFICATION TEST. PCM Verification Test.