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Line Pressure Control (LPC) Solenoid: Notes

The Line Pressure Control (LPC) solenoid is a Variable Force Solenoid (VFS) that varies hydraulic pressure by actuating a hydraulic valve.

The TCM  applies variable current to the LPC  solenoid which varies pressure in the VFS5 hydraulic circuit to the Main Regulator Valve. Refer to HYDRAULIC CIRCUITS  for information.

The LPC  solenoid uses inversely proportional operation. As the current from the TCM  decreases, the pressure from the solenoid increases. As the current from the TCM  increases, the pressure from the solenoid decreases. The LPC  solenoid is supplied hydraulic pressure from the SREG circuit.

With zero current, the LPC  solenoid fully opens the hydraulic valve which applies the maximum amount of hydraulic pressure to the Main Regulator Valve through the VFS5 hydraulic circuit and applies maximum line pressure in the PUMP hydraulic circuit. With maximum current to the solenoid, the hydraulic valve fully closes the outlet port for minimum pressure to the VFS5 hydraulic circuit to lower the line pressure in the PUMP hydraulic circuit.