DTC B1648 (KA/KC model) (2016 2017 2018 2019 2020)

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 (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.

   One-Push - KEYLESS ACCESS CONTROL UNIT - 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. EXT FR AS+, EXT FR AS- line output check

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

   -2. Disconnect the following connector.

   Right-front LF antenna/initiator 2P connector

   -3. Turn the vehicle to the ON mode.

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

   Test condition	Vehicle ON mode Right-front LF antenna/initiator 2P connector: disconnected
   Test circuit	EXT FR AS+, EXT FR AS-
   Test point 1	Right-front LF antenna/initiator 2P connector No. 2 (WHT)
   Test point 2	Right-front LF antenna/initiator 2P connector No. 1 (YEL)

   Courtesy of HONDA, U.S.A., INC.

   Is there voltage?

   YES 

   Replace the right-front LF antenna/initiator .

   NO 

   Go to step 3.

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

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

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

   Terminal A	Right-front LF antenna/initiator 2P connector No. 2 (WHT)
   Terminal B	Right-front LF antenna/initiator 2P connector No. 1 (YEL)

   Courtesy of HONDA, U.S.A., INC.

   -3. Disconnect the following connector.

   Keyless access/TPMS control unit connector A (32P)

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

   Test condition	Vehicle OFF (LOCK) mode Keyless access/TPMS control unit connector A (32P): disconnected Right-front LF antenna/initiator 2P connector: disconnected
   Test circuit	EXT FR AS+, EXT FR AS-
   Test point 1	Keyless access/TPMS control unit connector A (32P) No. 12 (WHT)
   Test point 2	Keyless access/TPMS control unit connector A (32P) No. 28 (YEL)

   Courtesy of HONDA, U.S.A., INC.

   Is there continuity?

   YES 

   The EXT FR AS+ and EXT FR AS- wires are OK. Replace the keyless access/TPMS control unit .

   NO 

   Repair an open or high resistance in the wire.