P0627-FUEL PUMP CONTROL CIRCUIT OPEN

Special Tools: Click to display a list of tools used in this procedure

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

When Monitored:
With the engine running and the battery voltage greater than 10.4 Volts.
Set Condition:
The Powertrain Control Module (PCM) detects that the actual state of the fuel pump control does not match the intended state.

Possible Causes
(K31) FUEL PUMP CONTROL CIRCUIT SHORTED TO VOLTAGE
(K31) FUEL PUMP CONTROL CIRCUIT SHORTED TO GROUND
(K31) FUEL PUMP CONTROL CIRCUIT OPEN OR HIGH RESISTANCE
TOTALLY INTEGRATED POWER MODULE (TIPM)
POWERTRAIN CONTROL MODULE (PCM)

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).

1. DIAGNOSTIC TROUBLE CODE (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.	Using the scan tool, read the active DTCs.

Does the scan tool display P0627-FUEL PUMP CONTROL CIRCUIT/OPEN?

Yes

Go To 2

Test complete, the condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.
Perform the INTERMITTENT CONDITION diagnostic procedure. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).

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

1.	Turn the ignition off.

2.	Disconnect the Totally Integrated Power Module (TIPM) C1 harness connector.

3.	Disconnect the Powertrain Control Module (PCM) C1 harness connector.

4.	Turn the ignition on.

5.	Measure the voltage of the (K31) Fuel Pump Control circuit in the Totally Integrated Power Module (TIPM) C1 harness connector.

Is there any voltage present?

Yes

Repair the short to voltage in the (K31) Fuel Pump Control circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).

Go To 3

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

1.	Turn the ignition off.

2.	Measure the resistance between ground and the (K31) Fuel Pump Control circuit in the Totally Integrated Power Module (TIPM) C1 harness connector.

Is the resistance below 100 Ohms?

Yes

Repair the short to ground in the (K31) Fuel Pump Control circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).

Go To 4

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

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 the GPEC Diagnostic Adaptor to perform the diagnosis.

1.	Connect the Adapter, GPEC Diagnostic 10436 .

2.	Measure the resistance of the (K31) Fuel Pump Control circuit between the Totally Integrated Power Module (TIPM) C1 harness connector and the GPEC Adaptor.

Is the resistance below 5.0 Ohms?

Yes

Go To 5

Repair the open or high resistance in the (K31) Fuel Pump Control circuit.
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).

5. TOTALLY INTEGRATED POWER MODULE (TIPM)

1.	Connect the Powertrain Control Module (PCM) C1 harness connector.

2.	Connect a jumper wire between ground and the (K31) Fuel Pump Control circuit in the Totally Integrated Power Module (TIPM) C1 harness connector.

3.	Turn the ignition on.

4.	Using the scan tool, select View DTCs.

Is the status Active for the Fuel Pump Control circuit shorted low DTC?

Yes

Replace the Totally Integrated Power Module (TIPM) in accordance with the Service Information.
Perform the BODY VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Totally Integrated Power (TIPM) - Standard Procedure).

Go To 6

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 POWERTRAIN VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).

Replace and program the Powertrain Control Module (PCM) in accordance with the Service Information. (Refer to 08 - Electrical/8E - Electronic Control Modules/MODULE, Powertrain Control - Removal) .
Perform the POWERTRAIN VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).

P0627-FUEL PUMP CONTROL CIRCUIT OPEN

Possible Causes