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DTC P2123

DTC P2123  : APP Sensor A (TP Sensor D) Circuit High Voltage

NOTE: Before you troubleshoot, review the general troubleshooting information .
DTC Description Confirmed DTC Pending DTC
P2123 APP Sensor A (TP Sensor D) Circuit High 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
    APP Sensor A Voltage More than 4.9 V    

    Data List

    Do the current condition(s) match the threshold?

    YES 

    The failure is duplicated. Go to step 2.

    NO 

    Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the APP sensor 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 (APP sensor, others)

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

    -2. Disconnect the following connector.

    APP sensor 6P connector

    -3. Turn the vehicle to the ON mode.

    -4. Measure the voltage between test points 1 and 2.

    Test condition Vehicle ON mode
      APP sensor 6P connector: disconnected
    Test point 1 APP sensor 6P connector (female terminals) No. 4:
    Test point 2 APP sensor 6P connector (female terminals) No. 5:
    GHH385404Courtesy of HONDA, U.S.A., INC.

    Is there about 5.0 V?

    YES 

    Replace the accelerator pedal module .

    NO 

    Go to step 3.

  3. Open wire check (SG4 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 A (50P)

    -4. Connect terminals A and B with a jumper wire.

    Terminal A APP sensor 6P connector (female terminals) No. 5:
    Terminal B Body ground
    GHH385406Courtesy of HONDA, U.S.A., INC.

    -5. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      APP sensor 6P connector: disconnected
      PCM connector A (50P): disconnected
      APP sensor 6P connector No. 5: jumped to body ground
    Test point 1 PCM connector A (50P) No. 46
    Test point 2 Body ground

    Is there continuity?

    YES 

    The SG4 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 P2123 goes away and the PCM was substituted, replace the original PCM .

    NO 

    Repair an open in the SG4 wire between the PCM (A46) and the APP sensor.