P0135

DTC P0135: A/F Sensor (Sensor 1) Heater Circuit Malfunction

1. Reset the ECM with the HDS.
2. Start the engine.
3. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P0135 indicated?

YES - Go to step 4.

NO - Intermittent failure, system is OK at this time.
Check for poor connections or loose terminals at C102 (located under the right side of the dash), the A/F sensor relay, the A/F sensor (Sensor 1), and the ECM.

4. Check these fuses:

- No.16 (30 A) fuse in the under-hood fuse/relay box.
- No.14 (30 A) fuse in the under-dash fuse/relay box.
- No.4 (7.5 A) in the 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 5.




5. Measure voltage between ECM connector terminals D5 and B20, 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 6.




6. Measure voltage between ECM connector terminals D11 and 820.

Is there battery voltage?

YES - Go to step 7.

NO - Go to step 11.

7. Turn the ignition switch OFF.
8. Disconnect ECM connector A (32P).
9. Turn the ignition switch ON (II).




10. Connect ECM connector terminal All to body ground with a jumper wire, then measure voltage between ECM connector terminals D5 and 820.

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 or short in the wire between the A/F sensor (Sensor 1) and the ECM (D5).

11. Turn the ignition switch OFF.
12. Disconnect ECM connector D (16P) and the A/F sensor (Sensor 1) 4P connector.




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

Is there continuity?

YES - Repair short in the wire between the A/F sensor relay, A/F sensor (Sensor 1) and the ECM (D11).

NO - Go to step 14.

14. Turn the ignition switch ON (II).




15. Measure voltage between ECM connector terminals A11 and B20.

Is there battery voltage?

YES - Repair open in the wire between the ECM (D11) and the A/F sensor (Sensor 1).

NO - Go to step 16.

16. Check for continuity in the wires between the A/F sensor relay 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.