DTC Troubleshooting: P0112 (125-1)

DTC P0112:  IAT Sensor 1 Low Voltage

1.Turn the ignition switch ON (II).

2.Check IAT SENSOR 1 in the DATA LIST with the HDS.

Is about 0.097 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 MAF sensor/IAT sensor 1 and the ECM.n


3.Turn the ignition switch OFF.

4.Disconnect the MAF sensor/IAT sensor 1 5P connector.

5.Turn the ignition switch ON (II).

6.Check IAT SENSOR 1 in the DATA LIST with the HDS.

Is about 0.097 V or less indicated?


YES - Go to 7.


NO - Go to 10.


7.Turn the ignition switch OFF, and wait 30 seconds.

8.Disconnect ECM connector No. 1 (96P).

9.Check for continuity between MAF sensor/IAT sensor 1 5P connector terminal No. 1 and body ground.

 

Is there continuity?


YES - Repair short in the wire between the MAF sensor/IAT sensor 2 and ECM connector No. 1 terminal No. 88, then go to 12.


NO - Go to 16.


10.Turn the ignition switch OFF.

11.Replace the MAF sensor/IAT sensor 1.

12.Reconnect all connectors.

13.Turn the ignition switch ON (II).

14.Reset the ECM with the HDS.

15.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 MAF sensor/IAT sensor 1 and the ECM, 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


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

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 MAF sensor/IAT sensor 1 and the ECM, then go to 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.


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