DTC Troubleshooting
DTC P0134: Rear A/F Sensor (Bank 1, Sensor 1) Heater System MalfunctionDTC 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.
- 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 ON (II).
2. Clear the DTC with the HDS.
3. Start the engine, and let it idle without load (in Park or neutral) for at least 1 minute.
4. Check for Temporary DTCs or 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 PGM-FI subrelay (LAF),and the PCM.
5. Turn the ignition switch OFF.
6. Jump the SCS line with the HDS.
7. Disconnect the A/F sensor (Sensor 1) 6P connector.
8. Disconnect PCM connector B (49P).
9. Check for continuity between A/F sensor (Sensor 1) 6P connector terminal No. 4 and PCM connector terminal B13(B14)*.
Is there continuity?
YES - Go to step 10.
NO - Repair open in the wire between the PCM (B13 (B14)*) and the A/F sensor (Sensor 1), then go to step 14.
10. Reconnect PCM connector B (49P).
11. Start the engine, and let it idle without load (in Park or neutral) for at least 1 minute.
12. Measure 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 20.
NO - Go to step 13.
13. Replace the A/F sensor (Sensor 1).
14. Reconnect all connectors.
15. Turn the ignition switch ON (II).
16. Reset the PCM with the HDS.
17. Do the PCM idle learn procedure.
18. Check for Temporary DTCs or 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 PGM-FI subrelay (LAF), and the PCM, then go to step 1.
NO - Go to step 19.
19. 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 Temporary DTCs or DTCs were indicated in step 18, go to the indicated DTCs troubleshooting.
NO - If the screen indicates FAILED, check for poor connections or loose terminals at the A/F sensor (Sensor 1), the PGM-FI subrelay (LAF), and the PCM, then go to step 1. If the screen indicates NOT COMPLETED, keep idling until a result comes on.
20. Turn the ignition switch ON (II).
21. Reconnect all connectors.
22. Update the PCM if it does not have the latest software, or substitute a known-good PCM.
23. Start the engine, and let it idle without load (in Park or neutral) for at least 1 minute.
24. Check for Temporary DTCs or 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 PGM-FI subrelay (LAF), and the PCM. If the PCM was updated, substitute a known-good PCM, then go to step 23. If the PCM was substituted, go to step 1.
NO - Go to step 25.
25. 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. If any other Temporary DTCs or DTCs were indicated in step 24, go to the indicated DTCs troubleshooting.
NO - If the screen indicates FAILED, check for poor -connections or loose terminals at the A/F sensor (Sensor 1), the PGM-FI subrelay (LAF), and the PCM. If the PCM was updated, substitute a known-good PCM, then go to step 23. If the PCM was substituted, go to step 1. If the screen indicates NOT COMPLETED, go to step 23.