DTC : B1FAB

DTC B1FAB  : Left rear heater current abnormal high (second row seat)

DTC (Second Row Seat Heater Control Unit)

NOTE: 

• If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A - Go to: Body Electrical Troubleshooting - B-CAN System Diagnosis Test Mode A - Initial Communication and DTC Checks .
• The seat heater control unit does not turn on the seat heater until the seat core temperature is 85 degrees or less. Make sure the seat core temperature is below 85 degrees before troubleshooting.

1. Problem verification

   -1. Clear the DTCs with the HDS.

   Clear DTCs

   - 2. Turn the vehicle to the OFF (LOCK) mode and then the ON mode.

   - 3. Check for DTCs with the HDS.

   DTC Description	DTC
   B1FAB Left rear heater current abnormal high (second row seat)

   Is DTC B1FAB indicated?

   YES 

   Go to step 2.

   NO 

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

2. DTC check 1

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

   - 2. Disconnect the following connector.

   Left second row seat heater connector B (3P)

   - 3. Turn the vehicle to the ON mode.

   - 4. Clear the DTCs with the HDS.

   Clear DTCs

   - 5. Check for DTCs with the HDS.

   DTC Description	DTC
   B1FAB Left rear heater current abnormal high (second row seat)

   Is DTC B1FAB indicated?

   YES 

   Go to step 3.

   NO 

   Go to step 4.

3. Short wire check (RR L HEATER line)

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

   - 2. Disconnect the following connector.

   Second row seat heater control unit 14P connector

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

   Test condition	Vehicle OFF (LOCK) mode Second row seat heater control unit 14P connector: disconnected Left second row seat heater connector B (3P): disconnected
   Test point 1	Second row seat heater control unit 14P connector No. 1 - Refer to: Second Row Seat Heater Control Unit Connector for Inputs and Outputs (2016 2017 2018) or Second Row Seat Heater Control Unit Connector for Inputs and Outputs (2019 2020 2021) .
   Test point 2	Body ground

   Is there continuity?

   YES 

   Repair a short in the wire.

   NO 

   Replace the Second Row Seat Heater Control Unit - Removal and Installation .

4. Short wire check (HTR CUSH/BACK line)

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

   - 2. Disconnect the following connector.

   Left second row seat heater connector A (4P)

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

   Test condition	Vehicle OFF (LOCK) mode Second row seat heater control unit 14P connector: disconnected Left second row seat heater connector A (4P): disconnected Left second row seat heater connector B (3P): disconnected
   Test point 1	Left second row seat heater connector B (3P) No. 2
   Test point 2	Body ground

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

   Is there continuity?

   YES 

   Repair a short in the wire.

   NO 

   Go to step 5.

5. DTC check 2

   -1. Reconnect the following connector.

   Left second row seat heater connector B (3P)

   - 2. Turn the vehicle to the ON mode.

   - 3. Clear the DTCs with the HDS.

   Clear DTCs

   - 4. Check for DTCs with the HDS.

   DTC Description	DTC
   B1FAB Left rear heater current abnormal high (second row seat)

   Is DTC B1FAB indicated?

   YES 

   Replace the left Second Row Seat-Back Cushion Heater .

   NO 

   Replace the left Second Row Seat Cushion Heater .