Control Solenoid (MV 2)
| ITEM | DESCRIPTION |
|---|---|
| A | Solenoid in locked (energized) condition - park lock released |
| B | Solenoid in unlocked (deenergized) condition - park lock engaged |
| 1 | Solenoid |
| 2 | Claw - locked |
| 3 | Piston |
| 4 | Claw - unlocked |
A control solenoid MV 2 (Magnetic Valve 2) is located in the valve block. The solenoid is controlled by the TCM and converts electrical signals into hydraulic control signals to control the electronic park lock function
The control solenoid is an on/off solenoid which is controlled by the TCM by switching the solenoid to earth.
When the park position is deselected, control solenoid MV2 resets the parking lock valve in the Mechatronic valve block. This is achieved by the TCM providing the ground for the solenoid which is energized, releasing the claws from retaining the park lock piston. Main fluid pressure acting on the parking lock piston, pushes the piston back to release the lock.
When the park position is selected, control solenoid MV2 is deenergized. The fluid pressure at the parking lock cylinder piston is vented and the mechanical interlock of the piston is opened. A pre-tensioned torsion spring at the park lock disc pulls the piston into the "park" position where the piston engages with the control solenoid claws and is locked in the park position. An emergency release wire cable can be used to release the parking lock manually if an electrical failure occurs.
The resistance of the solenoid coil winding for solenoid is 25 Ohms at 20 °C (68 °F).
When the neutral "N" position is selected and the engine is turned off, the fluid pressure at the park lock cylinder piston is released. The current supply to the control solenoid MV2 remains. The park lock cylinder piston is still held in the unlocked position by the spring force acting on the park lock disc, preventing the park lock plate from engaging the parking lock. This allows the vehicle to be moved when the engine is not running for a short time. Should the battery voltage fall below the level required to maintain the solenoid in the energized condition, the park lock will be engaged.