ABS (Antilock Brake System)

DTC C1253 Motor Relay Circuit

CIRCUIT DESCRIPTION
The ABS and TRAC motor relay supplies power to the hydraulic brake booster pump motor. While the ABS & TRAC & VSC are activated, the ECU switches the motor relay ON and operates the hydraulic brake booster pump motor.





DETECTING CONDITION

Fail safe function:
If trouble occurs in the ABS and TRAC motor relay circuit, the ECU cuts off current to the ABS solenoid relay and prohibits ABS & TRAC & VSC controls and the brake system becomes normal.





WIRING DIAGRAM

Step 1:

Step 2:

Step 3:

Step 4:

Step 5:

Step 6:

INSPECTION PROCEDURE
Start the inspection from step 1, in case of using the LEXUS hand-held tester and start from step 3, in cas of not using LEXUS hand-held tester