Always On - Malfunction In ECU

DETECTING CONDITIONS

HINT: There is a case that LEXUS hand-held tester cannot be used when ECU is abnormal.

Fail safe function:
If trouble occurs in the ECU, the ECU cuts off current to the ABS solenoid relay and prohibits ABS & BA & TRAC & VSC controls. When fail safe function in ABS system is activated, "VSC TRAC" warning light and "VSC OFF" indicator light tight up.




WIRING DIAGRAM

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INSPECTION PROCEDURE