DTC P1172: A/F Sensor (Sensor 1) Circuit Out of Range High
- Turn the ignition switch to ON (II).
- Clear the DTC with the HDS.
- 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.
- Monitor the OBD STATUS for DTC P1172 in the DTCs MENU with the HDS.
Does the screen indicate FAILED?
YES: Go to step 5.
NO: If the HDS indicates PASSED, 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. If the HDS indicates EXECUTING, keep idling until a result comes on. If the HDS indicates OUT OF CONDITION or NOT COMPLETED, go to step 3 and recheck.
- Turn the ignition switch to LOCK (0).
- Replace the A/F sensor (Sensor 1) (see A/F SENSOR REPLACEMENT ).
- Turn the ignition switch to ON (II).
- Reset the ECM/PCM with the HDS.
- Do ECM/PCM IDLE LEARN PROCEDURE .
- 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.
- Check for Pending or Confirmed DTCs with the HDS.
Is DTC P1172 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.
NO: Go to step 12.
- Monitor the OBD STATUS for DTC P1172 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 11, 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 EXECUTING, keep idling until a result comes on. If the HDS indicates OUT OF CONDITION or NOT COMPLETED, go to step 10.