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DTC B1647

DTC B1647  : Passenger's Door 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
B1647 Passenger's Door 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.

    One-Push - KEYLESS ACCESS CONTROL UNIT - SELF CHECK

    -3. Do the SELF CHECK.

    -4. Check for DTCs with the HDS.

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

    Is DTC B1647 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 FR AS+, EXT FR AS- lines)

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

    -2. Disconnect the following connectors.

    Body control module connector F (36P)
    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 F (36P): disconnected Front passenger's door outer handle 8P connector: disconnected
    Test point 1 Body control module connector F (36P) No. 12
    Test point 2 Body ground
    Test point 1 Body control module connector F (36P) No. 30
    Test point 2 Body ground

    Is there continuity?

    YES 

    Repair a short to ground in the wire.

    NO 

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

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

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

    Test condition Vehicle OFF (LOCK) mode Body control module connector F (36P): disconnected Front passenger's door outer handle 8P connector: disconnected
    Test point 1 Body control module connector F (36P) No. 12
    Test point 2 Body control module connector F (36P) No. 30

    Is there continuity?

    YES 

    Repair a short in EXT FR AS+ wire to EXT FR AS- wire.

    NO 

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

  4. Body control module EXT FR AS+, EXT FR AS- line output check

    -1. Reconnect the following connector.

    Body control module connector F (36P)

    -2. Turn the vehicle to the ON mode.

    -3. Select KEYLESS ACCESS CONTROL UNIT from the ONE-PUSH START system select menu with the HDS, and enter FUNCTIONAL TESTS.

    One-Push - KEYLESS ACCESS CONTROL UNIT - FUNCTIONAL TESTS

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

    Test condition Vehicle ON mode Front passenger's door outer handle 8P connector: disconnected
    Test point 1 Front passenger's door outer handle 8P connector (female terminals) No. 2:
    Test point 2 Front passenger's door outer handle 8P connector (female terminals) No. 6:
    GHH429136Courtesy of HONDA, U.S.A., INC.

    -5. Select FRONT PASSENGER (DOOR) ANTENNA L DC OUTPUT with the HDS.

    Is there voltage?

    YES 

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

    NO 

    Replace the body control module .