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DTC B1645

DTC B1645  : Driver'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
B1645 Driver'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
    B1645 Driver's Door LF Antenna Circuit Short  

    Is DTC B1645 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 DR+, EXT FR DR- lines)

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

    -2. Disconnect the following connectors.

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

    Is there continuity?

    YES 

    Repair a short to ground in the wire.

    NO 

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

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

    -1. 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 

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

    NO 

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

  4. Body control module EXT FR DR+, EXT FR DR- 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 Driver's door outer handle 8P connector: disconnected
    Test point 1 Driver's door outer handle 8P connector (female terminals) No. 2:
    Test point 2 Driver's door outer handle 8P connector (female terminals) No. 6:
    GHH429127Courtesy of HONDA, U.S.A., INC.

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

    Is there voltage?

    YES 

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

    NO 

    Replace the body control module .