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DTC P0112

DTC P0112  : IAT Sensor 1 Circuit Low Voltage

NOTE: Before you troubleshoot, review the general troubleshooting information .
DTC Description Confirmed DTC Pending DTC
P0112 IAT Sensor 1 Circuit Low Voltage    

DTC (PGM-FI)

  1. Problem verification

    -1. Turn the vehicle to the ON mode.

    -2. Check the parameter(s) below with the HDS.

    Signal Threshold Current conditions
    Values Unit Values Unit
    IAT Sensor (1) Voltage Less than 0.08 V    

    Data List

    Do the current condition(s) match the threshold?

    YES 

    Go to step 2.

    NO 

    Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at MAF sensor/IAT sensor 1 and the PCM. If the on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the on-board snapshot .

  2. Determine possible failure area (MAF sensor/IAT sensor 1, others)

    -1. Turn the vehicle to the OFF (LOCK) mode.

    -2. Disconnect the following connector.

    MAF sensor/IAT sensor 1 5P connector

    -3. Turn the vehicle to the ON mode.

    -4. Check the parameter(s) below with the HDS.

    Signal Threshold Current conditions
    Values Unit Values Unit
    IAT Sensor (1) Voltage Less than 0.08 V    

    Data List

    Do the current condition(s) match the threshold?

    YES 

    Go to step 3.

    NO 

    Replace MAF sensor/IAT sensor 1 .

  3. Shorted wire check (IAT1(TA) line)

    -1. Turn the vehicle to the OFF (LOCK) mode.

    -2. Jump the SCS line with the HDS, and wait more than 1 minute.

    -3. Disconnect the following connector.

    PCM connector E (80P)

    -4. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      MAF sensor/IAT sensor 1 5P connector: disconnected
      PCM connector E (80P): disconnected
    Test point 1 MAF sensor/IAT sensor 1 5P connector (female terminals) No. 4:
    Test point 2 Body ground
    GHH384809Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Repair a short in the IAT1(TA) wire between the PCM (E53) and MAF sensor/IAT sensor 1.

    NO 

    The IAT1(TA) wire is OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM , then recheck. If DTC P0112 goes away and the PCM was substituted, replace the original PCM .