P0135

DTC P0135: A/F Sensor (Sensor 1) Heater Circuit Malfunction (2004-2005 models)

1. NOTE:
- information marked with an asterisk (*) applies to 2002-2003 models.
- Information marked with double asterisk (**)applies to 2004-2005 models.

2. Start the engine.

Is DTC P1166* (P0135)** Indicated?

YES - Go to step 3.

NO - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the A/F sensor relay, the A/F sensor (Sensor 1), and the ECM.

3. Check the these fuses:

- No.14 OPTION (30 A) fuse in under-hood fuse/relay box.
- No.2 +B LAF (A/F) HEATER (20 A) fuse in under-dash fuse/relay box.
- No.4 ACG (10 A) in under-dash fuse/relay box.

Are any of the fuses blown?

YES - Repair short in the wire between the A/F sensor relay and the fuses.

NO - Go to step 4.




4. Measure voltage between ECM connector terminals A1 and A24, 30 seconds after the ignition switch is turned ON (II).

Is there battery voltage?

YES - Update the ECM if it does not have the latest software, or substitute a known-good ECM, then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM.

NO - Go to step 5.




5. Measure voltage between ECM connector terminals A22 and A24.

Is there battery voltage?

YES - Go to step 6.

NO - Go to step 10.

6. Turn the ignition switch OFF.
7. Disconnect ECM connector (31P).
8. Turn the ignition switch ON (II).




9. Connect ECM connector terminal E8 to body ground with a jumper wire, then measure voltage between ECM connector terminals A1 and A24.

Is there battery voltage?

YES - Update the ECM if it does not have the latest software, or substitute a known-good ECM, then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM.

NO - Repair open in the wire between the A/F sensor (Sensor 1) and ECM (A1).

10. Turn the ignition switch OFF.
11. Disconnect the ECM connector A (31P) and the A/F sensor (Sensor 1) 4P connector.




12. Check for continuity between the A/F sensor (Sensor 1) 4P connector terminal No.3 and body ground.

Is there continuity?

YES - Repair short in the wire between the A/F sensor relay, A/F sensor (Sensor 1) and ECM (A22).

No - Go to step 13.

13. Turn the ignition switch ON (II).




14. Measure voltage between ECM connector terminals E8 and A24.

Is there battery voltage?

YES - Repair open in the wire between the ECM (A22) and the A/F sensor (Sensor 1).

NO - Go to step 15.

15. Check for continuity in the wires between the A/F sensor and the fuses.

Is there continuity?

YES - The wires are OK. Replace the A/F sensor relay.

NO - Repair open in the wire between the A/F sensor relay and the fuses.