DTC C1257: Power Supply Drive Circuit [04/2018 -]: Procedure

1. Clear the DTCs.

   Refer to DTC CHECK / CLEAR [04/2018 -]

   Chassis > ABS/VSC/TRAC > Clear DTCs 

2. Turn the power switch off.
3. Turn the power switch on (IG).
4. Check if the same DTC is output.

   Refer to DTC CHECK / CLEAR [04/2018 -]

   Chassis > ABS/VSC/TRAC > Trouble Codes 

   Result

   Result	Proceed to
   DTC C1257 is output.	A
   DTCs C1241, C1242 and/or C1253 are output.	B

Result: 

A 

REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY. Refer to  REMOVAL [04/2018 - 08/2021]  , or refer to  REMOVAL [08/2021 -] 

Result: 

B 

REPAIR CIRCUITS INDICATED BY OUTPUT DTCS. Refer to  DIAGNOSTIC TROUBLE CODE CHART [04/2018 - 08/2019]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [08/2019 - 08/2020]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [08/2020 - 08/2021]  , or refer to  DIAGNOSTIC TROUBLE CODE CHART [08/2021 -]