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DTC B2639-87

DTC B2639-87  : Lost Communication With The Front Left Center Sensor

NOTE:  If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A .

DTC Description DTC
B2639-87 Lost Communication With The Front Left Center Sensor  

DTC (Parking and Back-Up Sensor Control Unit)

  1. Problem verification

    -1. Clear the DTCs with the HDS.

    -2. Turn the vehicle to the OFF (LOCK) mode and then the ON mode.

    -3. Turn the parking and back-up sensor switch to ON.

    -4. Wait for at least 6 seconds.

    -5. Check for DTCs with the HDS.

    DTC Description DTC
    B2639-87 Lost Communication With The Front Left Center Sensor  

    Is DTC B2639-87 indicated?

    YES 

    Go to step 2.

    NO 

    Intermittent failure, the system is OK at this time. Check for loose or poor connections.

  2. DTC check

    -1. Check for DTCs with the HDS.

    DTC Description DTC
    B2638-87 Lost Communication With The Front Left Corner Sensor  
    B2639-87 Lost Communication With The Front Left Center Sensor  
    B2640-87 Lost Communication With The Front Right Center Sensor  
    B2641-87 Lost Communication With The Front Right Corner Sensor  

    Are DTC B2638-87, B2639-87, B2640-87, and B2641-87 indicated?

    YES 

    Go to step 6.

    NO 

    Go to step 3.

    NO 

    Check for loose or poor connections. If OK, replace the parking and back-up sensor control unit .

  3. Left front center sensor check

    -1. Substitute a known-good left front center sensor .

    -2. Clear the DTCs with the HDS.

    -3. Turn the vehicle to the OFF (LOCK) mode and then the ON mode.

    -4. Turn the parking and back-up sensor switch to ON.

    -5. Wait for at least 6 seconds.

    -6. Check for DTCs with the HDS.

    DTC Description DTC
    B2639-87 Lost Communication With The Front Left Center Sensor  

    Is DTC B2639-87 indicated?

    YES 

    Go to step 4.

    NO 

    Replace the original left front center sensor .

  4. Shorted wire check (SOF CTR L line)

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

    -2. Disconnect the following connector.

    Left front center sensor 3P connector
    Parking and back-up sensor control unit 24P connector

    -3. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
    Left front center sensor 3P connector: disconnected
    Parking and back-up sensor control unit 24P connector: disconnected
    Test point 1 Left front center sensor 3P connector (female terminals) No. 2:
    Test point 2 Body ground
    GHH397406Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Repair a short to ground in SOF CTR L wire between the left front center sensor and the parking and back-up sensor control unit.

    NO 

    The SOF SIDE L wire is not shorted to ground, go to step 5.

  5. Open wire check (SOF CTR L line)

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

    Test condition Vehicle OFF (LOCK) mode
    Parking and back-up sensor control unit 24P connector: disconnected
    Left front center sensor 3P connector: disconnected
    Test point 1 Parking and back-up sensor control unit 24P connector No. 5
    Test point 2 Left front center sensor 3P connector (female terminals) No. 2:
    GHH397408Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The SOF CTR L wire is not opened, go to step 6.

    NO 

    Repair an open or high resistance in SOF CTR L wire between the parking and back-up sensor control unit and the left front center sensor.

  6. Open wire check (BOF SIDE L, E1 SIDE L lines)

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

    -2. Disconnect the following connectors.

    Parking and back-up sensor control unit 24P connector
    Left front center sensor 3P connector

    -3. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
    Parking and back-up sensor control unit 24P connector: disconnected
    Left front center sensor 3P connector: disconnected
    Test point 1 Parking and back-up sensor control unit 24P connector No. 2
    Test point 2 Left front center sensor 3P connector (female terminals) No. 3:
    GHH397410Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Repair an open or high resistance in E1 SIDE L wire between the parking and back-up sensor control unit and the left front center sensor.

    NO 

    Repair an open or high resistance in BOF SIDE L wire between the parking and back-up sensor control unit and the left front center sensor.