Circuit/System Description

The traction control prime (fill) and isolation (return) solenoid valves are located internally to the brake pressure modulator. The electronic brake control module activates the valve relay to supply voltage to the valve solenoids. This voltage is referred to as the system voltage. The electronic brake control module activates individual valve solenoids by grounding the valve solenoid control circuits. This verification is used to perform hydraulic checks at the normally open base brake valve, the front hydraulic circuit and the block.