GF80.20-P-1010GZ Tailgate Opening, Function

GF80.20-P-1010GZ Tailgate Opening, Function
- with CODE (890) Automatic rear-end door

Component Identification:

Function requirements, general
^ Circuit 30
^ System synchronized
^ Speed = 0 km/h
^ Spare tire holder open in 90° position (on model 164 with code (849) Spare tire holder/spare tire)

Open tailgate
the rear-end door function consists of the following functions:
^ Opening rear-end door via rear-end door handle switch
^ Opening rear-end door via rear-end door switch
^ Opening rear-end door via transmitter key

During the entire rear-end door opening operation, the rear-end door closing warning buzzer is actuated by the rear-end door closing control unit once each second.
The open status of the rear-end door is indicated by an LED integrated into the rear-end door switch (up to 31.5.07). On vehicles as of 1.6.07 the LED is eliminated.

Opening rear-end door via rear-end door handle switch

Additional function requirements
^ Central locking (CL) unlocked

Function sequence
Actuation of the tailgate handle switch is read in by the rear SAM control unit. The rear SAM control unit transmits this message to the CAN-B and simultaneously actuates the rear-end door locking unit to unlock the rear-end door. The tailgate closing control unit reads in the message and starts the tailgate hydraulic pump. The hydraulic cylinder is charged with oil and opens the tailgate with the multiple-joint hinge.
The rear-end door closing control unit controls the hydraulic operation via the opening angle recognition sensor. When the opening angle recognition sensor reaches the determined final switch-off angle, the rear-end door closing control module switches off the rear-end door hydraulic pump.

Opening rear-end door via rear-end door switch

Additional function requirements
^ Central locking (CL) unlocked

Function sequence
The request is read in by the left front door control unit via the rear-end door switch and transmitted to the CAN-B.
The rear SAM control unit transmits this message to the CAN-B and simultaneously actuates the rear-end door locking unit to unlock the rear-end door. The tailgate closing control unit reads in the message and starts the tailgate hydraulic pump. The hydraulic cylinder is charged with oil and opens the tailgate with the multiple-joint hinge.
The rear-end door closing control unit controls the hydraulic operation via the opening angle recognition sensor. When the opening angle recognition sensor reaches the determined final switch-off angle, the rear-end door closing control module switches off the rear-end door hydraulic pump.

When the rear-end door switch is actuated again, the opening operation is interrupted. The rear-end door remains in the current position.
The opening operation can be continued with any control element on the rear-end door remote control

Opening rear-end door via transmitter key

Function sequence
When the button on the transmitter key is actuated (t > 0.5 s), it transmits a radio signal to the roof antenna module; from there, it is relayed to the rear SAM control unit and stored on the CAN-B bus. The EIS control unit checks the access authorization of the transmitter key. If the transmitter key is valid, the rear SAM control unit actuates the rear-end door closing unit to unlock the rear-end door. The tailgate closing control unit reads in the message and starts the tailgate hydraulic pump. The hydraulic cylinder is charged with oil and opens the tailgate with the multiple-joint hinge.

The rear-end door closing control unit controls the hydraulic operation via the opening angle recognition sensor. When the opening angle recognition sensor reaches the determined final switch-off angle, the rear-end door closing control module switches off the rear-end door hydraulic pump.

When the button on the transmitter key is actuated again, the opening operation is interrupted. The rear-end door remains in the current position.
The opening operation can be continued with any control element on the rear-end door remote control.