DTC Troubleshooting

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.
- 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) until the radiator fan comes on.

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 A/F sensor relay (LAF), the under-dash fuse/relay box, and the PCM.

5. Turn the ignition switch OFF.
6. Replace the A/F sensor (Sensor 1).
7. Turn the ignition switch ON (II).
8. Reset the PCM with the HDS.
9. Do the PCM idle learn procedure.
10. Start the engine. Hold the engine speed at 3,000 rpm without load (in Park or neutral) until the radiator fan comes on, then let it idle.
11. 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 A/F sensor relay (LAF), the under-dash fuse/relay box, and the PCM, then Go to step 1.

NO - Go to step 12.

12. 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 11, 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), the underdash fuse/relay box, and the PCM, then Go to step 1. If the screen indicates NOT COMPLETED, keep idling until a result comes on.