DTC Troubleshooting
DTC Troubleshooting: P0135 (151-6), P0155 (152-6)
DTC P0135:
Rear A/F Sensor (Bank 1, Sensor 1) Heater Circuit Malfunction
DTC P0155:
Front A/F Sensor (Bank 2, Sensor 1) Heater Circuit Malfunction
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.
4. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P0135 and/or P0155* indicated?
YES -
Go to step 5.
NO -
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at A/F sensor (Sensor 1), the A/F sensor relay, and the PCM.�
5. Turn the ignition switch to LOCK (0).
6. Check these fuses:
- No. 4 LAF (A/F SENSOR) (15 A) fuse in the driver's under-dash fuse/relay box.
- No. 23 IGP (7.5 A) fuse in the driver's under-dash fuse/ relay box.
Are the fuses OK?
YES -
Go to step 7.
NO -
- If the No. 4 LAF (A/F SENSOR) (15 A) fuse is blown, go to step 23.
- If the No. 23 IGP (7.5 A) fuse is blown, go to step 28.
7. Remove the A/F sensor relay (A) from the driver's under-dash fuse/relay box.
8. Test the A/F sensor relay Power Relay Test.
Is the relay OK?
YES -
Go to step 9.
NO -
Replace the A/F sensor relay, then go to step 31.
9. Disconnect the A/F sensor (Sensor 1) 6P connector.
10. At the sensor side, measure the resistance between A/F sensor (Sensor 1) 6P connector terminals No. 1 and No. 2.
Is there 2.5-4.0 Ohms at the room temperature?
YES -
Go to step 11.
NO -
Go to step 30.
11. At the sensor side, check for continuity between each terminal of at the A/F sensor (Sensor 1) 6P connector and body ground.
Is there continuity to body ground at any terminal?
YES -
Go to step 30.
NO -
Go to step 12.
12. At the sensor side, check for continuity between A/F sensor (Sensor 1) 6P connector terminal No. 1 and each of the other terminals in the connectors individually.
Is there continuity?
YES -
Go to step 30.
NO -
Go to step 13.
13. Jump the SCS line with the HDS.
14. Disconnect PCM connector C (49P).
15. Check for continuity between PCM connector terminal C6 (C8)* and body ground.
Is there continuity?
YES -
Repair a short in the wire between the PCM(C6 (C8)*) and the A/F sensor (Sensor 1), then go to step 31.
NO -
Go to step 16.
16. Connect A/F sensor (Sensor 1) 6P connector terminal No. 2 to body ground with a jumper wire.
17. Check for continuity between PCM connector C6 (C8)*and body ground.
Is there continuity?
YES -
Go to step 18.
NO -
Repair an open in the wire between the PCM (C6 (C8)*) and the A/F sensor (Sensor 1), then go to step 31.
18. Connect A/F sensor relay 4P connector terminal No. 2 to body ground with a jumper wire.
19. Check for continuity between A/F sensor (Sensor 1) 6P connector terminal No. 1 and body ground.
Is there continuity?
YES -
Go to step 20.
NO -
Repair an open in the wire between the A/F sensor (Sensor 1) and the A/F sensor relay, then go to step 31.
20. Disconnect PCM connector A (49P).
21. Connect A/F sensor relay 4P connector terminal No. 3 to body ground with a jumper wire.
22. Check for continuity between PCM connector terminal A40 and body ground.
Is there continuity?
YES -
Go to step 37.
NO -
Repair an open in the wire between the A/F sensor relay and the PCM (A40), then go to step 31.
23. Remove the A/F sensor relay (A) from the driver's under-dash fuse/relay box.
24. Disconnect the front and rear A/F sensor (Sensor 1) 6P connectors.
25. Disconnect the front and rear secondary HO2S (Sensor 2) 4P connectors.
26. Disconnect the EVAP canister vent shut valve 2P connector.
27. Check for continuity between A/F sensor (Sensor 1) 6P connector terminal No. 1 and body ground.
Is there continuity?
YES -
Repair a short in the wire between the A/F sensor relay and the A/F sensor (Sensor 1). If the wire is OK, replace the driver's under-dash fuse/relay box Drivers Under-Dash Fuse/Relay Box (MICU) Removal/Installation. Also replace the No. 4 LAF (A/F SENSOR) (15 A) fuse, then go to step 31.
NO -
Replace the A/F sensor relay. Also replace the No. 4 LAF (A/F SENSOR) (15 A) fuse, then go to step 31.
28. Remove the A/F sensor relay (A) from the driver's under-dash fuse/relay box.
29. Check for continuity between A/F sensor relay 4P connector terminal No. 4 and body ground.
Is there continuity?
YES -
Replace the driver's under-dash fuse/relay box Drivers Under-Dash Fuse/Relay Box (MICU) Removal/Installation. Also replace the No. 23 IGP (7.5 A) fuse, then go to step 31.
NO -
Replace the A/F sensor relay. Also replace the No. 23 IGP (7.5 A) fuse, then go to step 31.
30. Replace the A/F sensor (Sensor 1) A/F Sensor Replacement.
31. Reconnect all connectors.
32. Turn the ignition switch to ON (II).
33. Reset the PCM with the HDS.
34. Do the PCM idle learn procedure PCM Idle Learn Procedure.
35. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P0135 and/or P0155* indicated?
YES -
Check for poor connections or loose terminals at the A/F sensor (Sensor 1), the A/F sensor relay, and the PCM, then go to step 1.
NO -
Go to step 36.
36. Monitor the OBD STATUS for DTC P0135 and/or P0155* in the DTCs MENU with the HDS.
Does the HDS indicate PASSED?
YES -
Troubleshooting is complete. If any other Pending or Confirmed DTCs were indicated in step 35, go to the indicated DTC's troubleshooting.�
NO -
If the HDS indicates FAILED, check for poor connections or loose terminals at the A/F sensor(Sensor 1), the A/F sensor relay, and the PCM, then go to step 1. If the HDS indicates NOT COMPLETED, keep idling until a result comes on.
37. Reconnect all connectors.
38. Update the PCM if it does not have the latest software PCM Update, or substitute a known-good PCM.
39. Start the engine, and let it idle.
40. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P0135 and/or P0155* indicated?
YES -
Check for poor connections or loose terminals at the A/F sensor (Sensor 1), the A/F sensor relay, and the PCM. If the PCM was updated, substitute a known-good PCM, then go to step 39. If the PCM was substituted, go to step 1.
NO -
Go to step 41.
41. Monitor the OBD STATUS for DTC P0135 in the DTCs MENU with the HDS.
Does the HDS 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 40, go to the indicated DTC's troubleshooting.�
NO -
If the HDS indicates FAILED, check for poor connections or loose terminals at the A/F sensor(Sensor 1), the A/F sensor relay, and the PCM. If the PCM was updated, substitute a known-good PCM, then go to step 39. If the PCM was substituted, go to step 1. If the HDS indicates NOT COMPLETED, keep idling until a result comes on.