DTC Troubleshooting

Control System DTCs

DTC Troubleshooting: P0111

DTC P0111 : IAT Sensor Circuit Range/Performance Problem

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information How To Troubleshoot The Fuel And Emissions Systems.

1. Connector visual check:

Connector visual check
-1. Check for poor or loose connections and terminals at these locations:
* MAF sensor/IAT sensor
* ECT sensor 1
* ECT sensor 2

Are the connections and terminals OK?
-YES- Go to step 2.
-NO- Repair the connections or terminals, then do the repair verification.

2. IAT sensor performance check (low temperature):

IAT sensor performance check (low temperature)
-1. Remove the MAF sensor/IAT sensor. Service and Repair

-2. Allow the MAF sensor/IAT sensor to cool to the ambient temperature.

-3. Note the ambient temperature.

-4. Connect the MAF sensor/IAT sensor to its 5P connector, but do not install it.

-5. Turn the ignition switch to ON (II).

-6. Quickly note the value of the IAT SENSOR in the DATA LIST with the HDS.

-7. Compare the value of IAT SENSOR to the ambient temperature.

Does the value of IAT SENSOR differ 5.4 °F (3 °C) or more from the ambient temperature?
-YES- Replace the MAF sensor/IAT sensor Service and Repair, then do the repair verification.
-NO- Go to step 3.

3. IAT sensor performance check (high temperature):

IAT sensor performance check (high temperature)
-1. Disconnect the following connector.





-2. Using a heat gun, blow hot air on the MAF sensor/IAT sensor for a few seconds. Do not apply the heat longer than a few seconds or you will damage the sensor.

-3. Connect the MAF sensor/IAT sensor to its 5P connector, but do not install it.

-4. Check the IAT SENSOR in the DATA LIST with the HDS.

Does the IAT SENSOR change 76 °F (42 °C) or more?
-YES- Replace the MAF sensor/IAT sensor Service and Repair, then do the repair verification.
-NO- Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the MAF sensor/IAT sensor and the ECM/PCM.

Repair verification:

-1. Turn the ignition switch to ON (II).

-2. Reset the ECM/PCM with the HDS How To Troubleshoot The Fuel And Emissions Systems.

-3. Do the ECM/PCM idle learn procedure. ECM/PCM Idle Learn Procedure

-4. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P0111 indicated?
-YES- Check for poor connections or loose terminals at the MAF sensor/IAT sensor and the ECM/PCM, then go to step 1.
-NO- Troubleshooting is complete. If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.