DTC B1657

DTC B1657  : Rear Bumper 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 (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
   B1657 Rear Bumper LF Antenna Circuit Short

   Is DTC B1657 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_TR+, EXT_TR- lines)

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

   -2. Disconnect the following connectors.

   Body control module connector F (36P)

   Rear bumper LF antenna 2P connector

   -3. Measure the resistance between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode Body control module connector F (36P): disconnected Rear bumper LF antenna 2P connector: disconnected
   Test point 1	Body control module connector F (36P) No. 14
   Test point 2	Body ground

   Test point 1	Body control module connector F (36P) No. 32
   Test point 2	Body ground

   Is there 1.0 MΩ or more?

   YES 

   The EXT_TR+ and EXT_TR- wires are not shorted. Go to step 3.

   NO 

   Repair a short to ground in the wire.

3. Shorted wire check (EXT_TR+ line to EXT_TR- line)

   -1. Measure the resistance between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode Body control module connector F (36P): disconnected Rear bumper LF antenna 2P connector: disconnected
   Test point 1	Body control module connector F (36P) No. 14
   Test point 2	Body control module connector F (36P) No. 32

   Is there 1.0 MΩ or more?

   YES 

   The EXT_TR+ and EXT_TR- wires are OK. Go to step 4.

   NO 

   Repair a short in EXT_TR+ wire to EXT_TR- wire.

4. Body control module EXT_TR+, EXT_TR- 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 Rear bumper LF antenna 2P connector: disconnected

   Test point 1	Rear bumper LF antenna 2P connector (female terminals) No. 2:
   Test point 2	Rear bumper LF antenna 2P connector (female terminals) No. 1:

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

   -5. Select CABIN REAR ANTENNA L DC OUTPUT with the HDS.

   Is there voltage?

   YES 

   Faulty rear bumper LF antenna; replace the rear bumper LF antenna .

   NO 

   Replace the body control module .