P0141

DTC P0141: Secondary HO(2)S (Sensor 2) Heater Circuit Malfunction

NOTE: Information marked with an asterisk (* ) applies to DTC P0141.

1. Reset the PCM.
2. Start the engine.

Is DTC P0135 or P0141 indicated?

YES - Go to step 3.

NO - Intermittent failure, system is OK at this time. Check for poor connections or loose wires at the primary HO(2)S (Sensor 1), the secondary HO(2)S (Sensor 2) and the PCM.

3. Turn the ignition switch OFF.
4. Disconnect the HO(2)S (primary or secondary *) (Sensor 1 or Sensor 2 * ) 4P connector.




5. At the HO(2)S side, measure resistance between HO(2)S 4P connector terminals No.3 and No.4.

Is there 10 - 40 Ohm?

YES - Go to step 6.

NO - Replace the primary HO(2)S (Sensor 1) or secondary HO(2)S (Sensor 2) *.




6. Check continuity between body ground and HO(2)S 4P connector terminals No.3 and No.4 individually.

Is there continuity?

YES - Replace the HO(2)S (primary or secondary *) (Sensor 1 or Sensor 2 *).

NO - Go to step 7.

7. Start the engine.




8. Measure voltage between HO(2)S 4P connector terminals No.3 and No.4.

Is there battery voltage?

YES - Go to step 9.

NO - Go to step 13.

9. Turn the ignition switch OFF.
10. Disconnect the negative cable from the battery.
11. Disconnect PCM connector C (31P) (PCM connector A, 32P) *.




12. Check for continuity between PCM connector terminal C1 (A8) * and body ground.

Is there continuity?

YES - Repair short in the wire between the PCM (C1, A8 * ) and the HO(2)S (primary or secondary * (Sensor 1, Sensor 2 *).

NO - Substitute a known-good PCM and recheck. If the symptom/indication goes away, replace the original PCM.




13. Measure voltage between HO(2)S 4P connector terminal No.4 and body ground.

Is there battery voltage?

YES - Go to step 14.

NO - Repair open in the wire between the primary HO(2)S (Sensor 1), secondary HO(2)S (Sensor 2) * and No.6 ECU (PCM) CRUISE CONTROL (15 A) fuse.

14. Turn the ignition switch OFF.
15. Reconnect the HO(2)S (primary or secondary *) (Sensor 1, Sensor 2 * ) 4P connector.
16. Disconnect the negative cable from the battery.
17. Disconnect PCM connector C (31P) (PCM connector A, 32P)*.
18. Reconnect the negative cable to the battery.
19. Turn the ignition switch ON (II).




20. Measure voltage between PCM connector terminals C1 (A8) * and B2.

Is there 0.1 V or less?

YES - Repair open in the wire between the PCM (C1, A8 * ) and HO(2)S (primary or secondary * (Sensor 1, Sensor 2 *).

NO - Substitute a known-good PCM and recheck. If the symptom/indication goes away, replace the original PCM.