DTC B278C-87: Power Source Control System Missing Message [10/2023 - ]: Procedure

1. Clear the DTCs.

   Body Electrical > Smart Access > Clear DTCs 

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  2

1. Check for DTCs.

   Body Electrical > Smart Access > Trouble Codes 

   Result

   Result	Proceed to
   B278C-87 is not output	A
   B278C-87 is output	B

Result: 

A 

USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2023 - ] 

Result: 

B 

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [10/2023 - ]