| DTC P0135: | Primary HO2S (Sensor 1) Heater Circuit Malfunction |
| 1. | Turn the ignition switch ON (II). |
| 2. | Do the DTC CLEAR in the CLEAR MENU with the HDS. |
| 3. | Start the engine. |
| 4. | Check for Temporary DTCs or DTCs in the DTCs MENU with the HDS. Is DTC P0135 indicated? YES - Go to 4. NO - Intermittent failure, system is OK at this time.Check for poor connections or loose terminals at the primary HO2S (Sensor 1) and the ECM.n |
| 5. | Check the No. 16 (7.5A) fuse in the under-dash fuse/relay box. Is the fuse OK? YES - Go to 6. NO - Repair short in the wire between the primary HO2S (Sensor 1) and No. 16 (7.5A) fuse, then go to 24. |
| 6. | Turn the ignition switch OFF. |
| 7. | Disconnect the primary HO2S (Sensor 1) 4P connector. |
| 8. | At the primary HO2S (Sensor 1) side, measure resistance between primary HO2S (Sensor 1) 4P connector terminals No. 3 and No. 4.
Is there about 8.1-9.9 W at room temperature? YES - Go to 9. NO - Go to 20. |
| 9. | At the primary HO2S (Sensor 1) side, check for continuity between body ground and primary HO2S (Sensor 1) 4P connector terminals No. 3 and No. 4 individually.
Is there continuity? YES - Go to 20. NO - Go to 10. |
| 10. | Turn the ignition switch ON (II). |
| 11. | Measure voltage between primary HO2S (Sensor 1) 4P connector terminals No. 3 and No. 4.
Is there battery voltage? YES - Go to 12. NO - Go to 15. |
| 12. | Turn the ignition switch OFF, and wait 10 seconds. |
| 13. | Connect the ECM test harness and the test pin box to the wire harness only, not to the ECM. |
| 14. | Check for continuity between test pin box terminal No. 130 and body ground. Is there continuity? YES - Repair short in the wire between the ECM connector No. 5 terminal No. 9 (test pin box terminal No. 130) and the primary HO2S (Sensor 1), then go to 22. NO - Go to 28. |
| 15. | Measure voltage between primary HO2S (Sensor 1) 4P connector terminal No. 3 and body ground.
Is there battery voltage? YES - Go to 16. NO - Repair open in the wire between the primary HO2S (Sensor 1) and No. 16 (7.5A) fuse, then go to 22. |
| 16. | Turn the ignition switch OFF, and wait 10 seconds. |
| 17. | Reconnect the primary HO2S (Sensor 1) 4P connector. |
| 18. | Connect the ECM test harness and the test pin box to the wire harness only, not to the ECM. |
| 19. | Measure voltage between test pin box terminals No. 130 and No. 4. Is there 0.1 V or less? YES - Repair open in the wire between the ECM connector No. 5 terminal No. 9 (test pin box terminal No. 130) and the primary HO2S (Sensor 1), then go to 22. NO - Go to 28. |
| 20. | Turn the ignition switch OFF. |
| 21. | Replace the primary HO2S (Sensor 1). |
| 22. | Reconnect all connectors. |
| 23. | Turn the ignition switch ON (II). |
| 24. | Do the ECM RESET in the CLEAR MENU with the HDS. |
| 25. | Do the ETCS learn procedure. |
| 26. | Start the engine. |
| 27. | Check for Temporary DTCs or DTCs in the DTCs MENU with the HDS. Are any Temporary DTCs or DTCs indicated? YES - If DTC P0135 is indicated, check for poor connections or loose terminals at the primary HO2S (Sensor 1) and the ECM, then go to 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC troubleshooting. NO - Troubleshooting is complete.n |
| 28. | Substitute a known-good ECM. |
| 29. | Start the engine. |
| 30. | Check for Temporary DTCs or DTCs in the DTCs MENU with the HDS. Are any Temporary DTCs or DTCs indicated? YES - If DTC P0135 is indicated, check for poor connections or loose terminals at the primary HO2S (Sensor 1) and the ECM, then go to 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC troubleshooting. |