3.2TL TYPE S V6-3.2L SOHC (2002)
Hydraulic Control Assembly - Antilock Brakes: Description and Operation
VSA
Modulator Unit
The modulator unit consists of the four inlet solenoid valves, four outlet solenoid valves, two front apply valves, two front dump valves, reservoir,
relied valves, regulator valve, ABS pump, VSA pump, and pump motor. The modulator controls the brake fluid pressure directly. It is a
circulating-type modulator because the brake fluid circulates through the caliper, the reservoir, and the master cylinder. The hydraulic control has
three modes: pressure intensifying, pressure retaining, and pressure reducing. The hydraulic circuit is an independent four channel type, one channel
for each wheel.
Modulator Operation
Conventional brake mode
The brake fluid is provided to the brake calipers through four inlet valves. In ABS mode, the VSA control unit drives four inlet valves, four outlet
valves, ABS pump, and pump motor the same as conventional ABS.
VSA mode (pressure intensifying operation)