Theory Of Operation

The monitoring of the pressure regulator and solenoid logic is used to detect a failure in the activation of the pressure regulators and solenoids. The pressure regulators are used to control the pressure to the clutches and the solenoids are used to activate the pressure to the park lock and to the position valve. The commanded currents of all regulators and solenoids are monitored. The monitoring consists of several monitoring strategies, transmission blocking, wrong driving direction, gear engagement of reverse gear while driving forward, unwanted engaging or disengaging of the park lock.