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DTC B1657

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DTC B1657  : Rear Bumper LF Antenna Circuit Short

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

DTC Description DTC
B1657 Rear bumper LF antenna circuit short  

DTC (Keyless Access Control Unit)

  1. Problem verification

    -1. Clear the DTCs with the HDS.

    -2. Select the KEYLESS ACCESS CONTROL UNIT from the ONE-PUSH START system select menu with the HDS, and enter the SELF CHECK.

    -3. Do the SELF CHECK.

    SELF CHECK

    Check for DTCs with the HDS.

    DTC Description DTC
    B1657 Rear bumper LF antenna circuit short  

    Is DTC B1657 indicated?

    YES 

    Go to step 2.

    NO 

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

  2. Shorted wire check (EXT TR+, EXT TR- lines)

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

    -2. Disconnect the following connectors.

    Body control module connector C (66P)
    Rear bumper LF antenna 2P connector

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

    Test condition Vehicle OFF (LOCK) mode
    Body control module connector C (66P): disconnected
    Rear bumper LF antenna 2P connector: disconnected
    Test point 1 Body control module connector C (66P) No. 33
    Test point 2 Body ground
    Test point 1 Body control module connector C (66P) No. 17
    Test point 2 Body ground

    Is there continuity?

    YES 

    Repair a short to ground in the wire.

    NO 

    The EXT TR+ and EXT TR- wires are not shorted. Go to step 3.

  3. Shorted wire check (EXT TR+ line to EXT TR- line)

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

    Test condition Vehicle OFF (LOCK) mode
    Body control module connector C (66P): disconnected
    Rear bumper LF antenna 2P connector: disconnected
    Test point 1 Body control module connector C (66P) No. 33
    Test point 2 Body control module connector C (66P) No. 17

    Is there continuity?

    YES 

    Repair a short between the wires.

    NO 

    The EXT TR+ and EXT TR- wires are OK. Go to step 4.

  4. Rear bumper LF antenna internal resistance check

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

    Test condition Vehicle OFF (LOCK) mode
    Body control module connector C (66P): disconnected
    Rear bumper LF antenna 2P connector: disconnected
    Test point 1 Rear bumper LF antenna 2P connector (female terminals) No. 1:
    Test point 2 Rear bumper LF antenna 2P connector (female terminals) No. 2:
    GHH396357Courtesy of HONDA, U.S.A., INC.

    Does the tester indicate over-range?

    YES 

    Replace the body control module .

    NO 

    Replace the rear bumper LF antenna .