K 2500 Truck 4WD V8-379 6.2L DSL VIN C FI (1989)
Hydraulic Control Assembly - Antilock Brakes: Description and Operation
Rear Wheel Antilock Control Module And Isolation/Dump Valve
The Isolation / Dump Valve maintains or increases hydraulic pressure to the rear brakes during severe brake application.
The Isolation / Dump Valve is made up of two valves, a dump valve which releases pressure into an accumulator during the dump cycle, and an isolation
valve which holds rear brake pressure.
The valve is controlled by a microcomputer which is part of the Electronic Control Unit (ECU).The ECU is mounted next to the master cylinder.
