Important: Transmission pressure control solenoid resistance should measure 3.5-8ohms when measured at 20°C (68°F).

The transmission pressure control solenoid (or force motor) is an electronic pressure regulator that controls pressure based on the current flow through its coil winding. The magnetic field produced by the coil moves the solenoid's internal valve which varies pressure to the pressure regulator valve.

The PCM controls the pressure control solenoid by commanding current between 0 and 1.1 amps. This changes the duty cycle of the solenoid, which can range between 0% and 60%. 1.1 amps correspond to the minimum line pressure, and 0 amps is the maximum line pressure (if the solenoid loses power, the transmission still has the maximum line pressure).

The PCM calculates the line pressure values, using inputs such as the throttle position sensor.

The pressure control solenoid takes the place of the throttle valve that was used on the past model transmissions.

If there is a difference between the amperage commanded by the PCM and the actual amperage, the diagnostic trouble code 073 will set. Unlike the pressure control solenoid on the HYDRA-MATIC 4L80-E, the 4L60-E pressure control solenoid does not pulse every 10 seconds for a cleaning cycle.