P0112

DTC P0112: IAT Sensor 1 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 IAT SENSOR 1 in the DATA LIST with the HDS.

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

YES - Go to step 3.

NO - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at IAT sensor 1 and the PCM.

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 356 degrees F (180 degrees 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 OFF.
8. Jump the SCS line with the HDS.
9. Disconnect PCM connector D(17P).




10. Check for continuity between MAF sensor/IAT sensor 1 5P connector terminal No. 2 and body ground.

Is there continuity?

YES - Repair short in the wire between IAT sensor 1 and the PCM (D9), then go to step 13.

NO - Go to step 18.

11. Turn the ignition switch OFF.
12. Reconnect all connectors.
13. Replace the MAF sensor/IAT sensor 1.
14. Turn the ignition switch ON (II).
15. Reset the PCM with the HDS.
16. Do the PCM idle learn procedure. Programming and Relearning
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 IAT sensor 1 and the PCM, then go to step 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.

NO - Troubleshooting is complete.

18. Update the PCM if it does not have the latest software, or substitute a known-good 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 IAT sensor 1 and the PCM, then go to step 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.

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