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DTC B1646

DTC B1646  : Driver's Door LF Antenna Circuit Open

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

DTC Description DTC
B1646 Driver's Door LF Antenna Circuit Open  

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.

    One-Push - KEYLESS ACCESS CONTROL UNIT - SELF CHECK

    -3. Do the SELF CHECK.

    -4. Check for DTCs with the HDS.

    DTC Description DTC
    B1646 Driver's Door LF Antenna Circuit Open  

    Is DTC B1646 indicated?

    YES 

    Go to step 2.

    NO 

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

  2. EXT FR DR+, EXT FR DR- line output check

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

    -2. Disconnect the following connector.

    Driver's door outer handle 8P connector

    -3. Turn the vehicle to the ON mode.

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

    Test condition Vehicle ON mode
    Driver's door outer handle 8P connector: disconnected
    Test point 1 Driver's door outer handle 8P connector No. 2
    Test point 2 Driver's door outer handle 8P connector No. 6
    GHH409667Courtesy of HONDA, U.S.A., INC.

    Is there voltage?

    YES 

    Faulty driver's door LF antenna; replace the driver's door outer handle .

    NO 

    Go to step 3.

  3. Open wire check (EXT FR DR+, EXT FR DR- lines)

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

    -2. Connect terminals A and B with a jumper wire.

    Terminal A Driver's door outer handle 8P connector No. 2
    Terminal B Driver's door outer handle 8P connector No. 6
    GHH409668Courtesy of HONDA, U.S.A., INC.

    -3. Disconnect the following connector.

    Body control module connector F (36P)

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

    Test condition Vehicle OFF (LOCK) mode
    Body control module connector F (36P): disconnected
    Driver's door outer handle 8P connector: disconnected
    Test point 1 Body control module connector F (36P) No. 13
    Test point 2 Body control module connector F (36P) No. 31

    Is there continuity?

    YES 

    The EXT FR DR+ and EXT FR DR- wires are OK. Replace the body control module .

    NO 

    Repair an open or high resistance in the wire.