DTC Troubleshooting
DTC Troubleshooting: P2238 (48)
DTC P2238:
A/F Sensor (Sensor 1) AFS+ 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.
4. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P2238 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 PCM.
5. Turn the ignition switch to LOCK (0).
6. Jump the SCS line with the HDS.
7. Disconnect the A/F sensor (Sensor 1) 4P connector.
8. Disconnect PCM connector C (44P).
9. Check for continuity between PCM connector terminal C29 and body ground.
Is there continuity?
YES -
Repair a short in the wire between the PCM (C29) and the A/F sensor (Sensor 1), then go to step 15.
NO -
Go to step 10.
10. Reconnect PCM connector C (44P).
11. Start the engine, and let it idle.
12. Measure the voltage between A/F sensor (Sensor 1) 4P connector terminal No. 1 and body ground.
Is there about 2.2 V?
YES -
Go to step 13.
NO -
Go to step 23.
13. Turn the ignition switch to LOCK (0).
14. Replace the A/F sensor (Sensor 1) A/F Sensor Replacement.
15. Reconnect all connectors.
16. Turn the ignition switch to ON (II).
17. Reset the PCM with the HDS.
18. Do the PCM idle learn procedure PCM Idle Learn Procedure.
19. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P2238 indicated?
YES -
Check for poor connections or loose terminals at the A/F sensor (Sensor 1) and the PCM, then go to step 1.
NO -
Go to step 20.
20. Monitor the OBD STATUS for DTC P2238 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 19, 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 PCM, then go to step 1. If the HDS indicates NOT COMPLETED, keep idling until a result come on.
21. Turn the ignition switch to LOCK (0).
22. Reconnect all connectors.
23. Update the PCM if it does not have the latest software PCM Update, or substitute a known-good PCM.
24. Start the engine, and let it idle.
25. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P2238 indicated?
YES -
If the PCM was updated, substitute a known-good PCM, then go to step 24. If the PCM was substituted, go to step 1.
NO -
Go to step 26.
26. Monitor the OBD STATUS for DTC P2238 in the DTCs MENU with the HDS.
Does the HDS indicate PASSED?
YES -
If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM Service and Repair. If any other Pending or Confirmed DTCs were indicated in step 25, go to the indicated DTC's troubleshooting.
NO -
If the HDS indicates FAILED, go to step 1. If the PCM was updated, substitute a known-good PCM, then go to step 24. If the PCM was substituted, go to step 1. If the HDS indicates NOT COMPLETED, keep idling idle until a result comes on.