Circuit/System Description

The line pressure control solenoid is part of the control solenoid valve assembly which has no serviceable parts. The normally high line pressure control solenoid regulates and directs the pressure control solenoid oil pressure to the isolator/pressure regulator valve. Increasing pressure control solenoid line pressure increases transmission line pressure. The Transmission Control Module varies the current to the line pressure control solenoid through a low side driver. Decreasing the current to the line pressure control solenoid increases line pressure control solenoid oil pressure by closing OFF the solenoid exhaust port. Increasing the current to the line pressure control solenoid decreases line pressure control oil pressure by opening the solenoid exhaust port. Line pressure control solenoid power is supplied by the Transmission Control Module through a high side driver. The high side driver protects the circuit and components from excessive current flow. If excessive current flow is detected, the high side driver will turn OFF. When the fault is corrected the high side driver will reset.