DTC B2456: Left Headlight ECU Variation Error [12/2017 - 10/2023]: Procedure

1. Clear the DTCs.

   Refer to DTC CHECK / CLEAR [12/2017 - 09/2018] , or refer to DTC CHECK / CLEAR [09/2018 - 10/2020] , or refer to DTC CHECK / CLEAR [10/2020 - 10/2023]

   Body Electrical > AFS > Clear DTCs 

2. Turn the engine switch on (IG).
3. Check for DTCs.

   Refer to DTC CHECK / CLEAR [12/2017 - 09/2018] , or refer to DTC CHECK / CLEAR [09/2018 - 10/2020] , or refer to DTC CHECK / CLEAR [10/2020 - 10/2023]

   Body Electrical > Passenger Seat > Trouble Codes 

   OK

   DTC B2456 is not output.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2017 - 09/2018]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [09/2018 - 10/2020]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2020 - 11/2021]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [11/2021 - 10/2022]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2022 - 10/2023] 

Result: 

NG 

See step  2

1. Check if the part number of the ECM installed to the vehicle is correct.

   OK

   Part number is correct.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPLACE ECM. Refer to  REMOVAL [12/2017 - 09/2018]  , or refer to  REMOVAL [09/2018 - 10/2020]  , or refer to  REMOVAL [10/2020 - 10/2022]  , or refer to  REMOVAL [10/2022 - 10/2023] 

Result: 

OK 

See step  3

1. Check if the part number of the main body ECU (multiplex network body ECU) installed to the vehicle is correct.

   OK

   Part number is correct.

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE HEADLIGHT ECU SUB-ASSEMBLY LH. Refer to  REMOVAL [12/2017 - 10/2020]  , or refer to  REMOVAL [10/2020 - ] 

Result: 

NG 

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to  REMOVAL [12/2017 - 09/2018]  , or refer to  REMOVAL [09/2018 - 10/2020]  , or refer to  REMOVAL [10/2020 - 10/2022]  , or refer to  REMOVAL [10/2022 - 10/2023]