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DTC B1648

DTC B1648  : Passenger'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
B1648 Passenger'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.

    -3. Do the SELF CHECK.

    SELF CHECK

    Check for DTCs with the HDS.

    DTC Description DTC
    B1648 Passenger's Door LF Antenna Circuit Open  

    Is DTC B1648 indicated?

    YES 

    Go to step 2.

    NO 

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

  2. Open wire check (EXT FR AS+, EXT FR AS- lines)

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

    -2. Disconnect the following connectors.

    Body control module connector C (66P)
    Front passenger's door outer handle 8P connector

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

    Test condition Vehicle OFF (LOCK) mode
    Body control module connector C (66P): disconnected
    Front passenger's door outer handle 8P connector: disconnected
    Test point 1 Body control module connector C (66P) No. 49
    Test point 2 Front passenger's door outer handle 8P connector (female terminals) No. 2:
    Test point 1 Body control module connector C (66P) No. 65
    Test point 2 Front passenger's door outer handle 8P connector (female terminals) No. 6:
    GHH387053Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The EXT FR AS+, EXT FR AS- wires are OK. Go to step 3.

    NO 

    Repair an open or high resistance in the wire.

  3. DTC check

    -1. Reconnect the following connector.

    Body control module connector C (66P)

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

    Terminal A Front passenger's door outer handle 8P connector (female terminals) No. 2:
    Terminal B Front passenger's door outer handle 8P connector (female terminals) No. 6:
    GHH387056Courtesy of HONDA, U.S.A., INC.

    -3. Remove all the keyless remotes from inside the vehicle. Hold them outside the open driver's window, at least 20 cm (7.9 in) away from the vehicle.

    -4. Press the power switch button at least 5 times.

    -5. Check for DTCs with the HDS.

    DTC Description DTC
    B1647 Passenger's Door LF Antenna Circuit Short  

    Is DTC B1647 indicated?

    YES 

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

    NO 

    Replace the body control module .