DTC Troubleshooting

DTC Troubleshooting: P2627, P2630

DTC P2627: Rear A/F Sensor (Bank 1, Sensor 1) LABEL Circuit Low Voltage

DTC P2630: Front A/F Sensor (Bank 2, Sensor 1) LABEL Circuit Low Voltage

NOTE:

- Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information. Initial Inspection and Diagnostic Overview

- Information marked with an asterisk (*) applies to the front bank (Bank 2).

1. Turn the ignition switch to ON (II).

2. Clear the DTC with the HDS.

3. Start the engine. Hold the engine speed at 3,000 rpm without load (in P or N) until the radiator fan comes on, then let it idle for 2 minutes.

4. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P2627 and/or P2630* indicated?
YES - Go to step 5.

NO - Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the A/F sensor (Sensor 1) and the PCM.


5. Turn the ignition switch to LOCK (0).

6. Jump the SCS line with the HDS.

7. Disconnect PCM connector C (49P).

8. Check for continuity between PCM connector terminal C13 (C29)* and body ground.

Is there continuity?
YES - Go to step 9.

NO - Go to step 17.






9. Disconnect the A/F sensor (Sensor 1) 8P connector.

10. Check for continuity between PCM connector terminal C13 (C29)* and body ground.

Is there continuity?
YES - Repair short in the wire between the PCM (C13 (C29)*) and the A/F sensor (Sensor 1), then go to step 12.

NO - Go to step 11.






11. Replace the A/F sensor (Sensor 1). A/F Sensor Replacement

12. Reconnect all connectors.

13. Turn the ignition switch to ON (II).

14. Reset the PCM with the HDS.

15. Do the PCM idle learn procedure. ECM/PCM Idle Learn Procedure

16. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P2627 and/or P2630* indicated?
YES - Check for poor connections or loose terminals at the A/F sensor (Sensor 1) and the PCM, then go to step 1.

NO - Troubleshooting is complete. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.


17. Reconnect all connectors.

18. Update the PCM if it does not have the latest software, ECM/PCM Update or substitute a known-good PCM. Initial Inspection and Diagnostic Overview

19. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P2627 and/or P2630* indicated?
YES - Check for poor connections or loose terminals at the A/F sensor (Sensor 1) and the PCM. If the PCM was updated, substitute a known-good PCM, Initial Inspection and Diagnostic Overview then recheck. If the PCM was substituted, go to step 1.

NO - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM. Service and Repair If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.