DTC Troubleshooting

DTC Troubleshooting: P0112

DTC P0112:

IAT Sensor 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), or press the engine start/stop button to select the ON mode.

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

Is about 356 °F (180 °C) or more, or 0.08 V or less 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 PCM.�

3. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

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

5. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

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

Is about 356 °F (180 °C) or more, or 0.08 V or less indicated?

YES -

Go to step 7.

NO -

Go to step 11.

7. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

8. Jump the SCS line with the HDS.

9. Disconnect PCM connector C (49P).

10. Check for continuity between MAF sensor/IAT sensor 5P connector terminal No. 2 and body ground.





Is there continuity?

YES -

Repair a short in the wire between the MAF sensor/IAT sensor and the PCM (C24), then go to step 13.

NO -

Go to step 18.

11. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

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

13. Reconnect all connectors.

14. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

15. Reset the PCM with the HDS.

16. Do the PCM idle learn procedure PCM Idle Learn Procedure.

17. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P0112 indicated?

YES -

Check for poor connections or loose terminals at the MAF sensor/IAT sensor and the PCM, then go to step 1.

NO -

Troubleshooting is complete. If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.�

18. Reconnect all connectors.

19. Update the PCM if it does not have the latest software PCM Update, or substitute a known-good PCM.

20. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P0112 indicated?

YES -

Check for poor connections or loose terminals at the MAF sensor/IAT sensor and the PCM. If the PCM was updated, substitute a known-good PCM, then recheck. If the PCM was substituted, go to step 1.

NO -

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 are indicated, go to the indicated DTC's troubleshooting.�