P0629

P0629-FUEL PUMP CONTROL CIRCUIT HIGH





For a complete wiring diagram Consult Diagrams/Electrical

- When Monitored:
With the ignition on and the Fuel Pump Relay command on.

- Set Condition:
The Engine Control Module (ECM) detects that the (K31) Fuel Pump Relay Control circuit is shorted to voltage for 2.0 seconds.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.Initial Inspection and Diagnostic Overview

Diagnostic Test

1. DTC IS ACTIVE
Ignition on, engine not running.
With the scan tool, Clear DTCs in the Engine Control Module (ECM).
Monitor the scan tool for at least two minutes.
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.Intermittent Condition

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




Turn the ignition off.
Remove the Fuel Pump Relay.
Disconnect the ECM harness connector.
Remove the ASD Relay from the PDC.
Connect a jumper wire between cavity 30 and cavity 87 of the ASD Relay Connector.
Turn the ignition on.
Measure the voltage of the (K31) Fuel Pump Relay Control circuit in the Fuel Pump Relay connector.
Is there any voltage present?

Yes

- Repair the (K31) Fuel Pump Relay Control circuit for a short to voltage.
- Perform the ECM Verification Test Ver. 1. Verification Tests

No

- Go to 3

3. (K31) FUEL PUMP RELAY CONTROL CIRCUIT SHORTED TO THE (A15) FUSED ASD RELAY OUTPUT CIRCUIT




Turn the ignition off.
Measure the resistance between the (K31) Fuel Pump Relay Control circuit and the (A15) Fused ASD Relay Output circuit in the Fuel Pump Relay connector.
Is the resistance above 10.0 ohms?

Yes

- Go to 4

No

- Repair the (K31) Fuel Pump Relay Control circuit for a short to the (A15) Fused ASD Relay Output circuit.
- Perform the ECM Verification Test Ver. 1. Verification Tests

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




Measure the resistance of the (K31) Fuel Pump Relay Control circuit between the Fuel Pump Relay connector and the Engine Control Module (ECM) harness connector.
Is the resistance below 10.0 ohms?

Yes

- Go to 5

No

- Repair the (K31) Fuel Pump Relay Control circuit for an open circuit or high resistance.
- Perform the ECM Verification Test Ver. 1. Verification Tests

5. FUEL PUMP RELAY
Connect the Engine Control Module (ECM) connector.
Install a substitute Fuel Pump Relay in place of the vehicle's Fuel Pump Relay.
Turn the ignition on.
With the scan tool, Clear DTCs.
Monitor the scan tool for at least two minutes.
With the scan tool, select View DTCs.
Is the status Active for this DTC?

Yes

- Go to 6

No

- Replace the Fuel Pump Relay.
- Perform the ECM Verification Test Ver. 1. Verification Tests

6. ENGINE CONTROL MODULE (ECM)
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Fuel Pump Relay and the Engine Control Module (ECM).
Look for any chafed, pierced, pinched, or partially broken wires.
Look for broken, bent, pushed out or corroded terminals.
Search for any Technical Service Bulletins that may apply.
Were any problems found?

Yes

- Repair as necessary.
- Perform the ECM Verification Test Ver. 1. Verification Tests

No

- Replace the Engine Control Module (ECM).
- Perform the ECM Verification Test Ver. 1. Verification Tests