DTC Troubleshooting
DTC Troubleshooting: P1157, P1157
DTC P1157:
A/F Sensor (Sensor 1) Circuit High 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 (*1) applies to '09-10 models and '11-12 models (M/T).
- Information marked with an asterisk (*2) applies to '11-12 models (A/T).
1. Turn the ignition switch to ON (II).
2. Clear the DTC with the HDS.
3. Start the engine, and wait about 20 seconds.
4. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P1157 indicated?
YES -
Go to step 5.
NO -
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the A/F sensor (Sensor 1) and the ECM/PCM.
5. Turn the ignition switch to LOCK (0).
6. Jump the SCS line with the HDS.
7. Remove the under-cowl panel Service and Repair.
8. Disconnect the A/F sensor (Sensor 1) 4P connector.
9. Disconnect ECM/PCM connector C (49P).
10. Check for continuity between A/F sensor (Sensor 1) 4P connector terminal No. 1 and ECM/PCM connector terminal C29.
Is there continuity?
YES -
Go to step 11.
NO -
Repair an open in the wire between the ECM/PCM (C29) and the A/F sensor (Sensor 1), then go to step 13.
11. Check for continuity between A/F sensor (Sensor 1) 4P connector terminal No. 2 and ECM/PCM connector terminal C30.
Is there continuity?
YES -
Go to step 12.
NO -
Repair an open in the wire between the ECM/PCM (C30) and the A/F sensor (Sensor 1), then go to step 13.
12. Replace the A/F sensor (Sensor 1) A/F Sensor Replacement.
13. Reconnect all connectors.
14. Turn the ignition switch to ON (II).
15. Reset the ECM/PCM with the HDS.
16. Do the ECM/PCM idle learn procedure ECM/PCM Idle Learn Procedure.
17. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P1157 indicated?
YES -
Check for poor connections or loose terminals at the A/F sensor (Sensor 1) and the ECM/PCM, then go to step 1. If the connections and the terminals are OK, go to step 19.
NO -
Go to step 18.
18. Monitor the OBD STATUS for DTC P1157 in the DTCs MENU with the HDS.
Does the HDS indicate PASSED?
YES -
Troubleshooting is complete. If any other Pending or Confirmed DTCs were indicated in step 17, go to the indicated DTC's troubleshooting.
NO -
If the HDS indicates FAILED, check for poor connections or loose terminals at the A/F sensor (Sensor 1) and the ECM/PCM, then go to step 1. If the HDS indicates NOT COMPLETED, go to step 16.
19. Update the ECM/PCM if it does not have the latest software ECM/PCM Update, or substitute a known-good ECM/PCM.
20. Start the engine, and let it idle.
21. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P1157 indicated?
YES -
If the ECM/PCM was updated, substitute a known-good ECM/PCM, then go to step 20. If the ECM/PCM was substituted, go to step 1.
NO -
Go to step 22.
22. Monitor the OBD STATUS for DTC P1157 in the DTCs MENU with the HDS.
Does the HDS 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 21, go to the indicated DTC's troubleshooting.
NO -
If the HDS indicates FAILED, go to step 1. If the ECM/PCM was updated, substitute a known-good ECM/PCM, then go to step 20. If the ECM/PCM was substituted, go to step 1. If the HDS indicates NOT COMPLETED, let the engine idle until a result comes on.