DTC P2128

2020 Honda HR-V LX, FWDSECTION DTC P2128

DTC P2128  : APP Sensor B (TP Sensor E) Circuit High Voltage

NOTE:  Before you troubleshoot, review the general troubleshooting information .

DTC Description Confirmed DTC Pending DTC Freeze Frame
P2128 APP Sensor B (TP Sensor E) 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 B More than 4.0 V    

    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 freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the freeze data/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 No. 1
    Test point 2 APP sensor 6P connector No. 2
    GHH434946Courtesy of HONDA, U.S.A., INC.

    Is there about 5.0 V?

    YES 

    Replace the APP sensor .

    NO 

    Go to step 3.

  3. Open wire check (SG5 line)

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

    -2. Jump the SCS line with the HDS.

    -3. Disconnect the following connector.

    PCM connector A (51P)

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

    Terminal A APP sensor 6P connector No. 2
    Terminal B Body ground
    GHH434947Courtesy 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
      APP sensor 6P connector No. 2: jumped to body ground
      PCM connector A (51P): disconnected
    Test point 1 PCM connector A (51P) No. 47
    Test point 2 Body ground

    Is there continuity?

    YES 

    The SG5 wire is OK. Update the PCM if it does not have the latest software, or substitute a known-good PCM , then recheck. If DTC P2128 goes away and the PCM was updated, troubleshooting is complete. If DTC P2128 goes away and the PCM was substituted, replace the original PCM .

    NO 

    Repair an open in the SG5 wire between the PCM (A47) and the APP sensor.

RENDER: 1.0x

NO RELATED

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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.