2012 Honda Insight BaseFACTORY OEM SERVICE PROCEDURE

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 (see GENERAL TROUBLESHOOTING INFORMATION ).
  1. Check for poor connections or loose terminals at ECT sensor 1, ECT sensor 2, and the MAF sensor/IAT sensor.

    Are the connections and terminals OK? 

    YES  -Go to step 2.

    NO  -Repair the connections or terminals, then go to step  15.

  2. Remove the MAF sensor/IAT sensor (see MAF SENSOR/IAT SENSOR REPLACEMENT ).
  3. Allow the MAF sensor/IAT sensor to cool to the ambient temperature.
  4. Note the ambient temperature.
  5. Connect the MAF sensor/IAT sensor to its 5P connector, but do not install it.
  6. Turn the ignition switch to ON (II).
  7. Note the value of the IAT SENSOR (2) quickly in the DATA LIST with the HDS.
  8. Compare the value of the IAT SENSOR (2) and the ambient temperature.

    Does the value of the IAT SENSOR (2) differ 5.4°F (3°C) or more from the ambient temperature? 

    YES  -Go to step  13.

    NO  -Go to step 9.

  9. Disconnect the MAF sensor/IAT sensor from its 5P connector.
  10. 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.
  11. Connect the MAF sensor/IAT sensor to its 5P connector, but do not install it.
  12. Check the IAT SENSOR (2) in the DATA LIST with the HDS.

    Does the IAT SENSOR (2) change 72°F (40°C) or more? 

    YES  -Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the MAF sensor/IAT sensor and the PCM.

    NO  -Go to step 13.

  13. Turn the ignition switch to LOCK (0).
  14. Replace the MAF sensor/IAT sensor (see MAF SENSOR/IAT SENSOR REPLACEMENT ).
  15. Turn the ignition switch to ON (II).
  16. Reset the PCM with the HDS.
  17. Do the PCM idle learn procedure (see PCM IDLE LEARN PROCEDURE ).
  18. 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 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 .

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.