P0141
DTC P0141: Rear Secondary HO2S (Bank 1, Sensor 2) Heater Circuit MalfunctionNOTE: 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.
4. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P0141 and/or P0161* indicated?
YES - Go to step 5.
NO - Intermittent failure, system is OK at this time Check for poor connections or loose terminals at the secondary HO2S (Sensor 2) and the PCM.
5. Turn the ignition switch OFF.
6. Check the No.9 LAFHT (15 A) fuse in the under-hood subfuse box.
Is the fuse blown?
YES - Repair short in the wire between the A/F sensors, A/F sensor relay and the fuse, then go to step 24.
NO - Go to step 7.
7. Disconnect the secondary HO2S (Sensor 2) 4P connector.
8. At the secondary HO2S (Sensor 2) side, measure resistance between secondary HO2S (Sensor 2) 4P connector terminals No.3 and No.4.
Is there 5.4 - 6.6 Ohms, at room temperature?
YES - Go to step 9.
NO - Go to step 23.
9. Check for continuity between body ground and secondary HO2S (Sensor 2) 4P connector terminals No.3 and No.4 individually.
Is there continuity?
YES - Go to step 23.
NO - Go to step 10.
10. Jump the SCS line with the HDS.
11. Disconnect PCM connector A (73P).
12. Check for continuity between PCM connector terminals A59 (A60)* and body ground.
Is there continuity?
YES - Repair short in the wire between the PCM (ASS (A60)*) and the secondary HO2S (Sensor 2), then go to step 24.
NO - Go to step 13.
13. Connect secondary HO2S (Sensor 2) 4P connector terminal No.3 to body ground with a jumper wire.
14. Check for continuity between PCM connector terminal A59 (A60)* and body ground.
Is there continuity?
YES - Go to step 15.
NO - Repair open in the wire between the PCM (A59 (A60)*) and the secondary HO2S (Sensor 2), then go to step 24.
15. Connect secondary HO2S (Sensor 2) 4P connector terminal No.4 to body ground with a jumper wire.
16. Remove the A/F sensor relay (A).
17. Check for continuity between A/F sensor relay terminal No.2 and body ground.
Is there continuity?
YES - Go to step 18.
NO - Repair open in the wire between the secondary HO2S (Sensor 2) and the A/F sensor relay, then go to step 24.
18. Disconnect PCM connector B (56P).
19. Check for continuity between PCM connector terminals B10 and body ground.
Is there continuity?
YES - Repair short in the wire between the PCM (B10) and the A/F sensor relay, then go to step 24.
NO - Go to step 20.
20. Connect A/F sensor relay terminal No.3 to body ground with a jumper wire.
21. Check for continuity between PCM connector terminal B10 and body ground.
Is there continuity?
YES - Go to step 22.
NO - Repair open in the wire between the PCM (B10) and the A/F sensor relay, then go to step 23.
22. Test the A/F sensor relay.
Is the A/F sensor relay OK?
YES - Go to step 29.
NO - Replace the A/F sensor relay, then go to step 24.
23. Replace the secondary HO2S (Sensor 2).
24. Turn the ignition switch ON (II).
25. Reset the PCM with the HDS.
26. Do the PCM idle learn procedure.
27. Check for Temporary DTCs or DTCs with the HDS.
Are any Temporary DTCs or DTCs indicated?
YES - If DTC P0141 and/or P0161* is indicated, check for poor connections or loose terminals at the secondary HO2S (Sensor 2) and the PCM, then go to step 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.
NO - Go to step 29.
28. Monitor the OBD STATUS for DTC P0141 and/or P0161* in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
YES - Troubleshooting is complete.
NO - If the screen indicates FAILED, check for poor connections or loose terminals at the secondary HO2S (Sensor 2) and the PCM, then go to step 1. If the screen indicates NOT COMPLETED, go to step 27 and recheck.
29. Update the PCM if it does not have the latest software, or substitute a known-good PCM.
30. Check for Temporary DTCs or DTCs with the HDS.
Are any Temporary DTCs or DTCs indicated?
YES - If DTC P0141 and/or P0161* is indicated, check for poor connections or loose terminals at the secondary HO2S (Sensor 2) and the PCM, then go to step 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.
NO - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM.