ON/OFF Solenoid Valves
WARNING: This page is about a different car, the 2016 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.
Transmission Control Solenoid Valve 8 and 9 are normally low, ON/OFF solenoids. These solenoids only direct hydraulic fluid pressure when commanded ON. Each solenoid receives 12 V from a high side driver internal to the TCM. Each solenoid valve has a control circuit to an individual low side driver internal to the TCM. The normal operating current range for these solenoids is between 0-1 A. If the TCM detects an electrical circuit malfunction or excessive current flow, the TCM turns off the high side driver to that solenoid and sets a DTC. The high side driver will reset when the circuit fault is corrected and the ignition switch is cycled.