Hydraulic Control Assembly - Antilock Brakes: Description and Operation

VALVE ASSEMBLY (BPMV)
The valve assembly provides brake fluid pressure modulation for each of the individual wheel circuits, as required, during an ABS/TCS event. During an ABS event, the valve assembly can maintain or reduce brake fluid pressure that is applied by the master cylinder. The valve assembly cannot increase pressure beyond what is applied by the master cylinder (driver). The valve assembly contains a motor-driven pump, ABS inlet and outlet valves, as well as TCS prime and isolation valves. With exception of the ABS Control Module (EBTCM), the valve assembly is not serviceable and should never be disassembled.
The valve assembly is an addition to the four-circuit diagonally-split hydraulic system found on vehicles without ABS.