DTC Troubleshooting
DTC Troubleshooting: P0137, P0137
DTC P0137:
Secondary HO2S (Sensor 2) Circuit Low Voltage
NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information Initial Inspection and Diagnostic Overview.
1. Turn the ignition switch to ON (II).
2. Clear the DTC with the HDS.
3. Start the engine. Hold the engine speed at 3,000 rpm without load (A/T in P or N, M/T in neutral) until the radiator fan comes on, then let it idle.
4. Monitor the OBD STATUS for DTC P0137 in the DTCs MENU with the HDS.
Does the screen indicate FAILED?
YES -
Go to step 5.
NO -
If the screen indicates PASSED, intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at secondary HO2S (Sensor 2) and the ECM/PCM. If the screen indicates EXECUTING or OUT OF CONDITION, keep idling until a result comes on.
5. Turn the ignition switch to LOCK (0).
6. Disconnect the secondary HO2S (Sensor 2) 4P connector.
7. Connect secondary HO2S (Sensor 2) 4P connector terminals No.1 and No.2 with a jumper wire.
8. Turn the ignition switch to ON (II).
9. Check the HO2S S2 OUTPUT VOLTAGE in the DATA LIST with the HDS.
Does the voltage stay at 0.12 V or less?
YES -
Go to step 10.
NO -
Go to step 22.
10. Turn the ignition switch to LOCK (0).
11. Remove the jumper wire from the secondary HO2S (Sensor 2) 4P connector.
12. Turn the ignition switch to ON (II).
13. Check HO2S S2 OUTPUT VOLTAGE in the DATA LIST with the HDS.
Is there about 5.0 V?
YES -
Go to step 14.
NO -
Go to step 18.
14. Turn the ignition switch to LOCK (0).
15. Jump the SCS line with the HDS.
16. Disconnect ECM/PCM connector B (49P).
17. Check for continuity between ECM/PCM connector terminal B37 and body ground.
Is there continuity?
YES -
Repair short in the wire between the ECM/PCM(B37) and secondary HO2S (Sensor 2), then go to step 24.
NO -
Go to step 31.
18. Turn the ignition switch to LOCK (0).
19. Jump the SCS line with the HDS.
20. Disconnect ECM/PCM connector B (49P).
21. Check for continuity between ECM/PCM connector terminal B36 and body ground.
Is there continuity?
YES -
Repair short in the wire between the ECM/PCM (B36) and secondary HO2S (Sensor 2), then go to step 24.
NO -
Go to step 31.
22. Turn the ignition switch to LOCK (0).
23. Replace secondary HO2S (Sensor 2) Secondary HO2S Replacement.
24. Reconnect all connectors.
25. Turn the ignition switch to ON (II).
26. Reset the ECM/PCM with the HDS.
27. Do the ECM/PCM idle learn procedure ECM/PCM Idle Learn Procedure (M/T).
28. Start the engine, and let it idle without load (A/T in P or N, M/T in neutral) until the radiator fan comes on.
29. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P0137 indicated?
YES -
Check for poor connections or loose terminals at secondary HO2S (Sensor 2) and the ECM/PCM, then go to step 1.
NO -
Go to step 30.
30. Monitor the OBD STATUS for DTC P0137 in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
YES -
Troubleshooting is complete. If any other Pending or Confirmed DTCs were indicated in step 29, go to the indicated DTC's troubleshooting.�
NO -
If the screen indicates FAILED, check for poor connections or loose terminals at secondary HO2S (Sensor 2) and the ECM/PCM, then go to step 1. If the screen indicates EXECUTING or OUT OF CONDITION, keep idling until a result comes on.
31. Reconnect all connectors.
32. Update the ECM/PCM if it does not have the latest software ECM/PCM Update (M/T), or substitute a known-good ECM/PCM.
33. Start the engine, and let it idle without load (A/T in P or N, M/T in neutral) until the radiator fan comes on.
34. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P0137 indicated?
YES -
Check for poor connections or loose terminals at secondary HO2S (Sensor 2) and the ECM/PCM. If the ECM/PCM was updated, substitute a known-good ECM/PCM, then go to step 33. If the ECM/PCM was substituted, go to step 1.
NO -
Go to step 35.
35. Monitor the OBD STATUS for DTC P0137 in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
YES -
If the ECM/PCM was updated, troubleshooting is complete. If the ECM/PCM was substituted, replace the original ECM/PCM Service and Repair. If any other Pending or Confirmed DTCs were indicated in step 34, go to the indicated DTC's troubleshooting.�
NO -
If the screen indicates FAILED, check for poor connections or loose terminals at secondary HO2S (Sensor 2) and the ECM/PCM. If the ECM/PCM was updated, substitute a known-good ECM/PCM, then go to step 33. If the ECM/PCM was substituted, go to step 1. If the screen indicates EXECUTING or OUT OF CONDITION, keep idling until a result comes on.