Remote trunk locking (RTL) function - GF80.20-P-0007A: Notes

MODELS 215, 220 with CODE (881b) Remote trunk locking (RTL)

Fig 1: Remote Trunk Locking (RTL) Function Diagram

Function overview

The remote trunk lid locking (RTL) function in comparison to remote trunk release (RTR) represents an extension to operating convenience. Remote trunk locking (RTL) makes it possible to open and close the trunk lid hydraulically. Models fitted with remote trunk locking (RTL) are equipped with additional hydraulics, a sensor and additional operating switches. The location and networking of the electric components corresponds to the conditions prevalent in the remote trunk release (RTR) feature. The extensions in the remote trunk locking (RTL) as compared with the remote trunk release (RTR) are highlighted in the block diagram. More detailed information can be ascertained from the reference table that follows.

Hydraulic opening of the trunk lid can be started with the following controls:

Via radio using the transmitter key (A8/1)
From inside the car by means of the remote trunk lid release switch (S20/1s6)
At the trunk lid using the trunk lid release switch (S15/1)

The trunk lid can be opened in this way as far as the end stop. The opening movement can also be stopped, however, at any desired point and also continued again.

As of 06/00: opening angle limitation : If the remote trunk lid release switch (S20/s16) is operated continuously for 5 seconds when the trunk lid is closed, the opening angle limitation is activated - and is deactivated if the remote trunk lid release switch (S20/s16) is operated again for another 5 seconds.

When the function is active, the trunk lid opens as far as the defined position.

Hydraulic closing of the trunk lid is possible by means of the following switches:

From inside the car by means of the remote trunk lid release switch (S20/1s6)
At the trunk lid using the RTL push-button (S62/26)

For safety reasons, it is not possible to close the trunk lid by means of the remote control using the transmitter key (A8/1).

During the hydraulic closing operation , the hydraulic system closes the trunk lid just far enough to enable the trunk lid to automatically engage in the catch as a result of its own weight. The RTL hydraulic pump (M51) is switched off before the trunk lid engages in the catch. The power closing system then performs the final closing of the trunk lid.

The entire control process for the opening and closing functions is conducted by the pneumatic control module (combined) (A37). The pneumatic control module (combined) (A37) scans the trunk lid opening angle detection sensor (B24/16) and is actuated via the

trunk lid open relay (K69/1) and
trunk lid close relay (K69/2)

and the hydraulic pump (RTL) (M51) . The two relays are responsible for actuating the electric motor in the hydraulic pump (RTL) (M51), switching it on and off as well as changing its direction of rotation.

When switched off the two hydraulic pump (RTL) (M51) terminals are connected to ground. To open the trunk lid a hydraulic pump (M51) terminal is switched from ground to terminal 30 by the trunk lid open relay (K69/1). When closing, the trunk lid close relay (K69/2) switches the corresponding connection at M51 from ground to terminal 30.

The hydraulic pump (RTL) (M51) builds up the pressure for the hydraulic ram . A multiple-jointed hinge is used to divert the straight-line motion of the hydraulic ram into a rotary movement, with the result that the trunk lid can be hydraulically opened and closed. The weight of the trunk lid is relieved through means of two installed gas-filled telescopic struts

Safety mechanism

With the trunk lid opening angle detection sensor (B24/16) the pneumatic control module (combined) (A37) controls the limit switch position and the hydraulic operation of the trunk lid. The hydraulic pump RTL (M51) is switched off when the specified limit stop angle position is reached.

With the aid of the trunk lid opening angle detection sensor (B24/16) the pneumatic control module (combined) (A37) analyzes not only the actual opening angle of the trunk lid, but it also registers any changes in speed in trunk lid movement. If the trunk lid encounters an obstacle or if a manual intervention takes place, the speed of the trunk lid is altered. In such an event the pneumatic control module (combined) (A37) stops the hydraulic opening motion and reverses the trunk lid's direction of movement during the closing procedure.

Manual operation of the trunk lid is also possible in an emergency, but necessitates greater physical effort as the hydraulic system also has to be moved. The trunk lid opening angle detection sensor (B24/16) does not require any recalibration after a manual intervention.

For safety reasons, the pneumatic control module (combined) (A37) switches the hydraulic pump RTL (M51) off after a maximum of two minutes continuous operation .

	Remote trunk locking (RTL), location of hydraulic components		GF80.20-P-0007-01A
	Remote trunk release (RTR), location of components		GF80.20-P-0006-01S
	Open trunk lid with remote control key, function		GF80.20-P-3010B
	Open trunk lid with interior switch, function		GF80.20-P-3012B
	Manually open trunk lid, function		GF80.20-P-3013B
	Close trunk lid, function		GF80.20-P-2006A
	Power-assisted trunk lid close, function		GF80.40-P-3002S
	Locking/unlocking trunk lid with mechanical key, function		GF80.20-P-3011S
	Trunk lid status indicator, function		GF80.20-P-4015S
	Trunk lid lock, position/task/design/function		GF80.20-P-4103S
	Pneumatic system equipment (PSE) control module (combined), position/task/design/function		GF80.20-P-4106S
	Hydraulic ram, position/task/design		GF80.20-P-4111A
	Trunk lid opening angle detection sensor, position/task/design/function		GF80.20-P-4113A
	Gas-filled telescopic struts, position/task		GF80.20-P-4114A
	Remote trunk locking hydraulic pump, position/task/design		GF80.20-P-4115A
	Trunk lid relay, position/task/design		GF80.20-P-4116A