P0141

DTC P0141: Secondary HO2S (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 C204 (located under the right side of the dash), C101 or C102 (located at the left side of the engine compartment), the Primary HO2S (Sensor 1), the Secondary HO2S (Sensor 2), and the ECM/PCM.

3. Check the No.6 ECU (PCM) CRUSE CONTROL (15 A) fuse in the driver's under-dash fuse/relay box.

Is DTC P0135 or P0141 indicated?

YES - Go to step 4.

NO - Replace the fuse and retest.

4. Turn the ignition switch OFF.
5. Disconnect the HO2S (primary or secondary *) (Sensor 1 or Sensor 2*) 4P connector.




6. At the HO2S side, measure resistance between HO2S 4P connector terminals No.3 and No.4.

Is there 5 - 15 ohm (10 - 40 ohm)*?

YES - Go to step 7.

NO - Replace the primary HO2S (Sensor 1) or secondary HO2S (Sensor 2)*.




7. Check continuity between body ground and HO2S 4P connector terminals No.3 and No.4 individually.

Is there continuity?

YES - Replace the HO2S (primary or secondary *) (Sensor 1 or Sensor 2*).

NO - Go to step 7.

8. Start the engine.




9. Measure voltage between HO2S 4P connector terminal No.3 and No.4.

Is there battery voltage?

YES - Go to step 10.

NO - Go to step 13.

10. Turn the ignition switch OFF.
11. Disconnect PCM connector C (31 P) (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 HO2S (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 HO2S 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 No.6 ECU (PCM) CRUSE CONTROL (15 A) fuse and the HO2S.

14. Turn the ignition switch OFF.
15. Reconnect the HO2S 4P connector.
16. Disconnect the PCM connector C (31P) (PCM connector A, 32P)*.
17. Turn the ignition switch ON (II).




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

Is there battery voltage?

YES - Substitute a known-good PCM and recheck. If the symptom/indication goes away, replace the original PCM.

NO - Repair open in the wire between the PCM (C1, A8*) and the HO2S (primary or secondary*) (Sensor 1, Sensor 2*).