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DTC 7-2

DTC 7-2





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NORMAL OPERATION
During the initial diagnosis, after the fail-safe relays are turned on, and during the regular diagnosis, the Anti-Lock Brake System (ABS) control unit monitors the voltage from the battery for the six solenoids (when the ABS is not functioning). If the detection circuit for the left-front solenoid detects 0 V, the ABS control unit keeps the ABS indicator light on after the engine is started. It turns the ABS indicator light on again if it detects 0 V aver the light goes off.

Possible Causes
- Front fail-safe relay stuck OFF
- Open circuit in the left-front solenoid drive circuits between the under-hood fuse/relay box and ABS control unit
- Short circuit to body ground in the left-front solenoid drive circuits between the solenoids and ABS control unit
- Faulty left-front solenoid drive transistor (ON) in the ABS control unit.

MORE NORMAL OPERATION
The ABS control unit momentarily outputs the ON signal to each solenoid (too momentary to turn the solenoid on) during the initial diagnosis, and each time the vehicle is driven, to check the voltage from the battery with the detection circuit. If the detection circuit for the left-front solenoids detects battery voltage at this time, the ABS control unit keeps the ABS indicator light on. It turns the ABS indicator light on again if it detects the~battery voltage when the vehicle is driven.

More Possible Causes
- Short circuit to power in the left-front solenoid drive circuits between the solenoids and ABS control unit.
- Faulty left-front solenoid drive transistor (OFF) in the ABS control unit.
- Short circuit to power in the left-front solenoid drive circuits in the modulator wire harness or solenoids.
- Short circuit to the left-front solenoid outlet circuit in the inlet circuit between the solenoids and ABS control unit.
- Short circuit to the right-front solenoid inlet or outlet circuit in the left-front solenoid inlet or outlet circuit between the solenoids and ABS control unit.