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, and let it idle without load (A/T in P or N, M/T in neutral) until the radiator fan comes on.
4. Check the HO2S S2 in the DATA LIST with the HDS.
Does the voltage stay at 0.05 V or less?
YES -
Go to step 5.
NO -
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the secondary HO2S (Sensor 2) and the ECM/PCM.�
5. Turn the ignition switch to LOCK (0).
6. Disconnect the secondary HO2S (Sensor 2) 4P connector.
7. Turn the ignition switch to ON (II).
8. Check the HO2S S2 in the DATA LIST with the HDS.
Does the voltage stay at 0.05 V or less?
YES -
Go to step 9.
NO -
Go to step 14.
9. Turn the ignition switch to LOCK (0).
10. Remove the under-cowl panel Service and Repair.
11. Jump the SCS line with the HDS.
12. Disconnect ECM/PCM connector B (49P).
13. Check for continuity between secondary HO2S (Sensor 2) 4P connector terminal No. 2 and body ground.
Is there continuity?
YES -
Repair short in the wire between the ECM/PCM (B36) and the secondary HO2S (Sensor 2), then go to step 16.
NO -
Go to step 24.
14. Turn the ignition switch to LOCK (0).
15. Replace the secondary HO2S (Sensor 2) Secondary HO2S Replacement.
16. Reconnect all connectors.
17. Turn the ignition switch to ON (II).
18. Reset the ECM/PCM with the HDS.
19. Do the ECM/PCM idle learn procedure ECM/PCM Idle Learn Procedure.
20. 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.
21. Test-drive under these conditions:
- Engine coolant temperature (ECT SENSOR 1) above 158 °F (70 °C)
- A/T in D (M/T in 4th gear)
- Engine speed between 1,500-3,000 rpm
- Drive 1 minute or more
22. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P0137 indicated?
YES -
Check for poor connections or loose terminals at the secondary HO2S (Sensor 2) and the ECM/PCM, then go to step 1.
NO -
Go to step 23.
23. 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 22, go to the indicated DTC's troubleshooting.�
NO -
If the screen indicates FAILED, check for poor connections or loose terminals at the secondary HO2S (Sensor 2) and the ECM/PCM, then go to step 1. If the screen indicates EXECUTING, keep driving until a result comes on. If the screen indicates OUT OF CONDITION or NOT COMPLETED, go to step 20.
24. Reconnect all connectors.
25. Update the ECM/PCM if it does not have the latest software ECM/PCM Update, or substitute a known-good ECM/PCM Initial Inspection and Diagnostic Overview.
26. 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.
27. Test-drive under these conditions:
- Engine coolant temperature (ECT SENSOR 1) above 158 °F (70 °C)
- A/T in D (M/T in 4th gear)
- Engine speed between 1,500-3,000 rpm
- Drive 1 minute or more
28. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P0137 indicated?
YES -
Check for poor connections or loose terminals at the secondary HO2S (Sensor 2) and the ECM/PCM. If the ECM/PCM was updated, substitute a known-good ECM/PCM Initial Inspection and Diagnostic Overview, then go to step 26. If the ECM/PCM was substituted, go to step 1.
NO -
Go to step 29.
29. 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 28, go to the indicated DTC's troubleshooting.�
NO -
If the screen indicates FAILED, check for poor connections or loose terminals at the secondary HO2S (Sensor 2) and the ECM/PCM. If the ECM/PCM was updated, substitute a known-good ECM/PCM Initial Inspection and Diagnostic Overview, then go to step 26. If the ECM/PCM was substituted, go to step 1. If the screen indicates EXECUTING, keep driving until a result comes on. If the screen indicates OUT OF CONDITION or NOT COMPLETED, go to step 26.