DTC Troubleshooting

DTC Troubleshooting: P0113

DTC P0113: IAT Sensor 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

1. Turn the ignition switch to ON (II).

2. Check the IAT SENSOR in the DATA LIST with the HDS.

Is about -40 °F (-40 °C) or less, or 4.92 V or more indicated?
YES - Go to step 3.

NO - Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the MAF sensor/IAT sensor and the ECM.


3. Turn the ignition switch to LOCK (0).

4. Disconnect the MAF sensor/IAT sensor 5P connector.

5. Connect MAF sensor/IAT sensor 5P connector terminals No. 4 and No. 5 with a jumper wire.

6. Turn the ignition switch to ON (II).

7. Check the IAT SENSOR in the DATA LIST with the HDS.

Is about -40 °F (-40 °C) or less, or 4.92 V or more indicated?
YES - Go to step 8.

NO - Go to step 20.






8. Turn the ignition switch to LOCK (0).

9. Remove the jumper wire from the MAF sensor/IAT sensor 5P connector.

10. Turn the ignition switch to ON (II).

11. Measure the voltage between MAF sensor/IAT sensor 5P connector terminal No. 5 and body ground.

Is there about 5 V?
YES - Go to step 12.

NO - Go to step 16.






12. Turn the ignition switch to LOCK (0).

13. Jump the SCS line with the HDS.

14. Disconnect ECM connector B (44P).

15. Check for continuity between MAF sensor/IAT sensor 5P connector terminal No. 4 and ECM connector terminal B33.

Is there continuity?
YES - Go to step 27.

NO - Repair open in the wire between the ECM (B33) and the MAF sensor/IAT sensor, then go to step 22.






16. Turn the ignition switch to LOCK (0).

17. Jump the SCS line with the HDS.

18. Disconnect ECM connector B (44P).

19. Check for continuity between MAF sensor/IAT sensor 5P connector terminal No. 5 and ECM connector terminal B31.

Is there continuity?
YES - Go to step 27.

NO - Repair open in the wire between the ECM (B31) and the MAF sensor/IAT sensor, then go to step 22.






20. Turn the ignition switch to LOCK (0).

21. Replace the MAF sensor/IAT sensor. Service and Repair

22. Reconnect all connectors.

23. Turn the ignition switch to ON (II).

24. Reset the ECM with the HDS.

25. Do the ECM idle learn procedure. ECM Idle Learn Procedure

26. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P0113 indicated?
YES - Check for poor connections or loose terminals at the MAF sensor/IAT sensor and the ECM, then go to step 1.

NO - Troubleshooting is complete. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.


27. Reconnect all connectors.

28. Update the ECM if it does not have the latest software, ECM Update or substitute a known-good ECM. Initial Inspection and Diagnostic Overview

29. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P0113 indicated?
YES - Check for poor connections or loose terminals at the MAF sensor/IAT sensor and the ECM. If the ECM was updated, substitute a known-good ECM, Initial Inspection and Diagnostic Overview then recheck. If the ECM was substituted, go to step 1.

NO - If the ECM was updated, troubleshooting is complete. If the ECM was substituted, replace the original ECM. Service and Repair If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.