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DTC P0112

DTC P0112 IAT sensor circuit low input
DETECTION CONDITION 
  • The PCM monitors the input voltage from the IAT sensor when the engine is running. If the input voltage is less than 0.16 V,  the PCM determines that the IAT sensor circuit input voltage is low.

Diagnostic support note 
  • This is a continuous monitor (CCM).
  • The MIL illuminates if the PCM detects the above malfunction condition in the first drive cycle.
  • FREEZE FRAME DATA (Mode 2/Mode 12) is available.
  • The DTC is stored in the PCM memory.
POSSIBLE CAUSE 
  • MAF/IAT sensor connector or terminals malfunction
  • Short to ground in wiring harness between MAF/IAT sensor terminal D and PCM terminal 1AT
  • IAT sensor malfunction
  • PCM connector or terminals malfunction
  • PCM malfunction
G07878102
DIAGNOSTIC PROCEDURE

STEP INSPECTION ACTION
1 VERIFY FREEZE FRAME DATA (MODE 12) HAS BEEN RECORDED 
  • Has the FREEZE FRAME DATA (Mode 12) been recorded?
 Yes Go to the next step.
No Record the FREEZE FRAME DATA (Mode 12) on the repair order, then go to the next step.
2 VERIFY RELATED REPAIR INFORMATION AVAILABILITY 
  • Verify related Service Bulletins and/or on-line repair information availability.
  • Is any related repair information available?
 Yes Perform repair or diagnosis according to the available repair information.
  • If the vehicle is not repaired, go to the next step.
No Go to the next step.
3 INSPECT MAF/IAT SENSOR CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition switch off.
  • Disconnect the MAF/IAT sensor connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector and/or terminals, then go to Step 7.
No Go to the next step.
4 INSPECT IAT SENSOR SIGNAL CIRCUIT FOR SHORT TO GROUND 
  • MAF/IAT sensor connector is disconnected.
  • Turn the ignition switch off.
  • Inspect for continuity between MAF/IAT sensor terminal D (wiring harness-side) and body ground.
  • Is there continuity?
 Yes If the short to ground circuit could be detected:
  • Repair or replace the wiring harness for a possible short to ground.

If the short to ground circuit could not be detected:
Go to Step 7.
No Go to the next step.
5 INSPECT IAT SENSOR 
 Yes Replace the MAF/IAT sensor, then go to Step 7.
(See MASS AIR FLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR REMOVAL/INSTALLATION ).
No Go to the next step.
6 INSPECT PCM CONNECTOR FOR POOR CONNECTION 
  • Turn the ignition switch off.
  • Disconnect the PCM connector.
  • Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector and/or terminals, then go to the next step.
No Go to the next step.
7 VERIFY TROUBLESHOOTING OF DTC P0112 COMPLETED 
  • Make sure to reconnect all disconnected connectors.
  • Clear the DTC from the PCM memory using the M-MDS.

    (See AFTER REPAIR PROCEDURE ).

  • Perform the KOEO or KOER self test.

    (See KOEO/KOER SELF TEST ).

  • Is the same DTC present?
 Yes Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION ).
No Go to the next step.
8 VERIFY AFTER REPAIR PROCEDURE 
 Yes Go to the applicable DTC inspection.
(See DTC TABLE ).
No DTC troubleshooting completed.
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