DTC Troubleshooting

DTC Troubleshooting: P0134, P0154

DTC P0134: Rear A/F Sensor (Bank 1, Sensor 1) Heater System Malfunction

DTC P0154: Front A/F Sensor (Bank 2, Sensor 1) Heater System Malfunction

NOTE:

- Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information. Reading and Clearing Diagnostic Trouble Codes

- If DTC P2251 and/or P2254* is stored at the same time as DTC P0134 and/or P0154*, troubleshoot DTC P2251 and/or P2254* first, then recheck for P0134 and/or P0154*.

- 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, and let it idle without load (in P or N) for at least 1 minute.

4. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P0134 and/or P0154* 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), the A/F sensor relay (LAF), and the PCM.


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

6. Jump the SCS line with the HDS.

7. Disconnect the A/F sensor (Sensor 1) 6P connector.

8. Disconnect PCM connector B (24P).

9. Connect A/F sensor (Sensor 1) 6P connector terminal No. 4 to body ground with a jumper wire.






10. Check for continuity between PCM connector terminal B12 (B20)* and body ground.

Is there continuity?
YES - Go to step 11.

NO - Repair open in the wire between the PCM (B12 (B20)*) and the A/F sensor (Sensor 1), then go to step 15.






11. Reconnect PCM connector B (24P).

12. Start the engine, and let it idle without load (in P or N) for at least 1 minute.

13. Measure the voltage between A/F sensor (Sensor 1) 6P connector terminal No. 4 and body ground.

Is there about 0.2 V or less?
YES - Go to step 21.

NO - Go to step 14.






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

15. Reconnect all connectors.

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

17. Reset the PCM with the HDS.

18. Do the PCM idle learn procedure. PCM Idle Learn Procedure

19. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P0134 and/or P0154* indicated?
YES - Check for poor connections or loose terminals at the A/F sensor (Sensor 1), the and the PCM, then go to step 1.

NO - Go to step 20.


20. Monitor the OBD STATUS for DTC P0134 and/or P0154* in the DTCs MENU with the HDS.

Does the screen indicate PASSED?
YES - Troubleshooting is complete. If any other Pending or Confirmed DTCs were indicated in step 19, go to the indicated DTC's troubleshooting.

NO - If the screen indicates FAILED, check for poor connections or loose terminals at the A/F sensor (Sensor 1), the A/F sensor relay (LAF), and the PCM, then go to step 1. If the screen indicates NOT COMPLETED, keep idling until a result comes on.


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

22. Reconnect all connectors.

23. Update the PCM if it does not have the latest software, PCM Update or substitute a known-good PCM. Reading and Clearing Diagnostic Trouble Codes

24. Start the engine, and let it idle without load (in P or N) for at least 1 minute.

25. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P0134 and/or P0154* indicated?
YES - Check for poor connections or loose terminals at the A/F sensor (Sensor 1), the A/F sensor relay (LAF), and the PCM. If the PCM was updated, substitute a known-good PCM, Reading and Clearing Diagnostic Trouble Codes then go to step 24. If the PCM was substituted, go to step 1.

NO - Go to step 26.


26. Monitor the OBD STATUS for DTC P0134 and/or P0154* in the DTCs MENU with the HDS.

Does the screen indicate PASSED?
YES - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM. Service and Repair If any other Pending or Confirmed DTCs were indicated in step 25, go to the indicated DTC's troubleshooting.

NO - If the screen indicates FAILED, check for poor connections or loose terminals at the A/F sensor (Sensor 1), the A/F sensor relay (LAF), and the PCM. If the PCM was updated, substitute a known-good PCM, Reading and Clearing Diagnostic Trouble Codes then go to step 24. If the PCM was substituted, go to step 1. If the screen indicates NOT COMPLETED, keep idling until a result comes on.