DTC Troubleshooting

DTC Troubleshooting: P0112, 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 ECM/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 ECM/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 short in the wire between the MAF sensor/IAT sensor and the ECM/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 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 P0112 indicated?

YES -

Check for poor connections or loose terminals at the MAF sensor/IAT sensor and the ECM/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 ECM/PCM if it does not have the latest software ECM/PCM Update, or substitute a known-good ECM/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 ECM/PCM. If the ECM/PCM was updated, substitute a known-good ECM/PCM, then recheck. If the ECM/PCM was substituted, go to step 1.

NO -

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