SOLENOID-PRESSURE CONTROL
DESCRIPTION
The pressure control solenoid (1) is mounted on the top of the valve body, next to the line pressure sensor (2).
The TCM utilizes a closed-loop system to control transmission line pressure. The system contains a variable force style solenoid, the Pressure Control Solenoid. The solenoid is duty cycle controlled by the TCM to vent the unnecessary line pressure supplied by the oil pump back to the sump. The system also contains a variable pressure style sensor, the Line Pressure Sensor, which is a direct input to the TCM. The line pressure solenoid monitors the transmission line pressure and completes the feedback loop to the TCM. The TCM uses this information to adjust its control of the pressure control solenoid to achieve the desired line pressure.
OPERATION
The pressure control solenoid (PCS) is a variable force (VFS) style solenoid. A VFS solenoid is an electro-hydraulic actuator, combining a solenoid and a regulating valve.
The transmission control module varies the current for the PCS, which varies the pressure in the line pressure hydraulic circuit. When the current (duty cycle) of the PCS is low, the pressure in the circuit is higher. At 0 current (0% duty cycle), the pressure is at the maximum value. Conversely, when the current is maximized (100% duty cycle), the pressure in the circuit is at the lowest possible value.
REMOVAL
1. Remove the valve body from the transmission. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 42RLE/VALVE BODY - REMOVAL)
2. Remove the electrical connectors from the pressure control solenoid (1) and the line pressure sensor (2).
3. Remove the screws (6) holding the pressure control solenoid (1) and line pressure sensor (2) to the valve body.
4. Remove the pressure control solenoid and line pressure sensor from the valve body.
INSTALLATION
1. Install the pressure control solenoid (1) and line pressure sensor (2) into the valve body.
2. Install the screws (6) to hold the pressure control solenoid (1) and line pressure sensor (2) to the valve body.
3. Install the electrical connectors to the pressure control solenoid (1) and the line pressure sensor (2).
4. Install the valve body into the transmission. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 42RLE/VALVE BODY - INSTALLATION)