DTC Troubleshooting
DTC Troubleshooting: P0137, P0157
DTC P0137: Rear Secondary HO2S (Bank 1, Sensor 2) Circuit Low Voltage
DTC P0157: Front Secondary HO2S (Bank 2, 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
- Information marked with an asterisk (*) applies to the front bank (Bank 2).
1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
2. Clear the DTC with the HDS.
3. Start the engine. Hold the engine speed at 3,000 rpm without load (in P or N) until the radiator fan comes on, then let it idle.
4. Check 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 secondary HO2S (Sensor 2) and the PCM.
5. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
6. Disconnect the secondary HO2S (Sensor 2) 4P connector.
7. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
8. Check 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 13.
9. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
10. Jump the SCS line with the HDS.
11. Disconnect PCM connector B (49P).
12. Check for continuity between secondary HO2S (Sensor 2) 4P connector terminal No. 1 and body ground.
Is there continuity?
YES - Repair short in the wire between the PCM (B25 (B16)*) and secondary HO2S (Sensor 2), then go to step 15.
NO - Go to step 23.
13. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
14. Replace secondary HO2S (Sensor 2). Secondary HO2S Replacement
15. Reconnect all connectors.
16. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
17. Reset the PCM with the HDS.
18. Do the PCM idle learn procedure. PCM Idle Learn Procedure
19. Start the engine, and let it idle without load (in P or N) until the radiator fan comes on.
20. Test-drive under these conditions:
- Engine coolant temperature (ECT SENSOR 1) above 158 °F (70 °C)
- Transmission in D
- Engine speed between 1,500-3,000 rpm
- Drive 1 minute or more
21. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P0137 and/or P0157* indicated?
YES - Check for poor connections or loose terminals at secondary HO2S (Sensor 2) and the PCM, then go to step 1.
NO - Go to step 22.
22. Monitor the OBD STATUS for DTC P0137 and/or P0157* 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 21, 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 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, go to step 19.
23. Reconnect all connectors.
24. Update the PCM if it does not have the latest software, PCM Update or substitute a known-good PCM. Initial Inspection and Diagnostic Overview
25. Start the engine, and let it idle without load (in P or N) until the radiator fan comes on.
26. Test-drive under these conditions:
- Engine coolant temperature (ECT SENSOR 1) above 158 °F (70 °C)
- Transmission in D
- Engine speed between 1,500-3,000 rpm
- Drive 1 minute or more
27. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P0137 and/or P0157* indicated?
YES - Check for poor connections or loose terminals at secondary HO2S (Sensor 2) and the PCM. If the PCM was updated, substitute a known-good PCM, Initial Inspection and Diagnostic Overview then go to step 25. If the PCM was substituted, go to step 1.
NO - Go to step 28.
28. Monitor the OBD STATUS for DTC P0137 and/or P0157* in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
YES - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM. PCM Replacement If any other Pending or Confirmed DTCs were indicated in step 27, 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 PCM. If the PCM was updated, substitute a known-good PCM, Initial Inspection and Diagnostic Overview then go to step 25. If the 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, go to step 25.