Variable Low and 1-2 Reverse and 4th Clutch Boost Valve
PCS 3 signal fluid pressure acts on a differential area of the variable low and 1-2 reverse and 4th clutch boost valve, moving the valve against variable low and 1-2 reverse and 4th clutch boost valve spring force to regulate VL 12 reverse clutch/4th clutch feed fluid into the VL 12 reverse clutch/4th clutch feedback circuit. As PCS 3 signal fluid pressure is increased to a given value, the variable low and 1-2 reverse and 4th clutch boost valve opens the VL 1-2 reverse clutch/4th clutch feedback circuit to exhaust. This results in the variable low and 1-2 reverse and 4th clutch regulator valve moving to the full feed position, sending full VL 12 reverse clutch/4th clutch feed pressure (full line pressure) to the variable low and 1-2 reverse clutch.