DTC Troubleshooting: P0112 (125)
DTC P0112:
 IAT Sensor 1 Low Voltage
NOTE: Before you troubleshoot, record all freeze data and review the general troubleshooting information.
  1. Turn the ignition switch ON (II).
  1. Check IAT SENSOR 1 in the DATA LIST with the HDS.
Is about 0.097 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 1 and the ECM.■
  1. Turn the ignition switch OFF.
  1. Disconnect the MAF sensor/IAT sensor 1 5P connector.
  1. Turn the ignition switch ON (II).
  1. Check IAT SENSOR 1 in the DATA LIST with the HDS.
Is about 0.097 V or less indicated?
YES -
Go to Step 7 .
NO -
Go to Step 10 .
  1. Turn the ignition switch OFF, and wait 2 minutes.
  1. Disconnect ECM connector No. 1 (96P).
  1. 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 1 and ECM connector No. 1 terminal No. 88, then go to Step 12 .
NO -
Go to Step 16 .
  1. Turn the ignition switch OFF.
  1. Reconnect all connectors.
  1. Turn the ignition switch ON (II).
  1. Reset the ECM with the HDS.
  1. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P0112 indicated?
YES -
Check for poor connections or loose terminals at the MAF sensor/IAT sensor 1 and the ECM, 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.■
  1. Reconnect all connectors.
  1. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P0112 indicated?
YES -
Check for poor connections or loose terminals at the MAF sensor/IAT sensor 1 and the ECM. If the ECM was updated, substitute a known-good ECM, then recheck. If the ECM was substituted, go to Step 1 .
NO -
If the ECM was updated, troubleshooting is complete. If the ECM was substituted, replace the original ECM. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.■