DTC Troubleshooting

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 356 °F(180 °C) or higher, 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 IAT sensor and the PCM.

3. Turn the ignition switch OFF.
4. Disconnect the IAT sensor 2P connector.
5. Turn the ignition switch ON (II).
6. Check the IAT SENSOR in the DATA LIST with the HDS.

Is about 356 °F(180 °C) or higher, 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 A (31P).




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

Is there continuity?

YES - Repair short in the wire between the IAT sensor and the PCM (A5), then Go to step 13.

NO - Go to step 18.

11. Turn the ignition switch OFF.
12. Replace the IAT sensor.
13. Reconnect all connectors.
14. Turn the ignition switch ON (II).
15. Reset the PCM with the HDS.
16. Do the PCM idle learn procedure.
17. Check for Temporary DTCs or DTCs with the HDS.

Is DTC P0112 indicated?

YES - Check for poor connections or loose terminals at the IAT sensor and the PCM, then Go to step 1.

NO - Troubleshooting is complete. If any other Temporary DTCs or DTCs are indicated, Go to the indicated DTC's troubleshooting.

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.

Is DTC P0112 indicated?

YES - Check for poor connections or loose terminals at the 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. If any other Temporary DTCs or DTCs are indicated, Go to the indicated DTC's troubleshooting.