DTC Troubleshooting: P0112 (10)

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.

1.Turn the ignition switch ON (II).

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

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


YES - Go to 3.


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


3.Turn the ignition switch OFF.

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

5.Turn the ignition switch ON (II).

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

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


YES - Go to 7.


NO - Go to 11.


7.Turn the ignition switch OFF.

8.Jump the SCS line with the HDS.

9.Disconnect ECM/PCM connector B (44P).

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 IAT sensor and ECM/PCM (B31), then go to 13.


NO - Go to 18.


11.Turn the ignition switch OFF.

12.Replace the MAF sesnor/IAT sensor.

13.Reconnect all connectors.

14.Turn the ignition switch ON (II).

15.Reset the ECM/PCM with the HDS.

16.Do the ECM/PCM idle learn procedure.

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

Are any Temporary DTCs or DTCs indicated?


YES - If DTC P0112 is indicated, check for poor connections or loose terminals at the IAT sensor and the ECM/PCM, then go to 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.


NO - Troubleshooting is complete.n

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

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

Are any Temporary DTCs or DTCs indicated?


YES - If DTC P0112 is indicated, check for poor connections or loose terminals at the IAT sensor and the ECM/PCM, then go to 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.


NO - If the ECM/PCM was updated, troubleshooting is complete. If the ECM/PCM was substituted, replace the original ECM/PCM.n