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 ECM/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, C102 (located at the left side of the engine compartment), the Primary HO(2)S (Sensor 1), the Secondary HO(2)S (Sensor 2), and the ECM/PCM.

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

Is the fuse OK?

YES - Go to step 4.

NO - Replace the fuse and retest.

4. Turn the ignition switch OFF.
5. Disconnect the HO(2)S (Primary or Secondary *) (Sensor 1 or Sensor 2 * ) 4P connector.




6. 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 (F23A4 SULEV engine: 2.0 - 20.0 Ohm) ?

YES - Go to step 7.

NO - Replace the Primary HO(2)S (Sensor 1) or Secondary HO(2)S (Sensor 2) *




7. Check for 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 8.

8. Turn the ignition switch ON (II).




9. Measure voltage between HO(2)S 4P connector terminals, 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 ECM/PCM connector C (31P) (ECM/PCM connector A, 32P) *.




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

Is there continuity?

YES - Repair short in the wire between the ECM/PCM (C1, A8 * ) and the HO(2)S (Primary or Secondary *) (Sensor 1, Sensor 2 *)

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




13. Measure voltage between HO(2)S 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 (ECM/PCM) CRUISE CONTROL (15 A) fuse and the HO(2)S.

14. Turn the ignition switch OFF.
15. Reconnect the HO(2)S 4P connector.
16. Disconnect ECM/PCM connector C (31P) (ECM/PCM connector A, 32P) *.
17. Turn the ignition switch ON (II).




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

Is there 0.1 V or less?

YES - Repair open in the wire between the ECM/PCM (C1, A8 * ) and the HO(2)S (Primary or Secondary *) (Sensor 1, Sensor 2 * ).

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