Open trunk lid with remote control key, function - GF80.20-P-3010T

MODEL 211.0 with CODE (881b) Remote trunk locking (RTL) 

Fig 1: Open Trunk Lid With Remote Control Key Communication Diagram

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

Open trunk lid with remote control key (A8/1) 

Function requirements 

• System synchronized
• Vehicle at rest
• Trunk lid not locked mechanically (no "Doorman position")

Operating procedure 

1. When the "Open trunk lid" button is actuated, the remote control key (A8/1) transmits a signal via radio. It is relayed by the left antenna amplifier module (A2/64) to the rear SAM control module with fuse and relay module (N10/2). This transmits the signal to the EIS control module (N73) for checking via the passenger compartment CAN bus.
2. The EIS control module (N73) relays the signal "Unlock trunk lid lock" to the rear SAM control module with fuse and relay module (N10/2) via the passenger compartment CAN bus. It actuates the trunk lid CL motor (M14/7) for unlocking the trunk lid lock.
3. The signal "Trunk lid lock unlocked" of the lock pawl rotary tumbler switch (S88/4) is relayed to the RTL control module (N121) by the rear SAM control module with fuse and relay module (N10/2) via the passenger compartment CAN bus.
4. The RTL control module (N121) actuates the trunk lid drive motor (M15/2).

   The position of the trunk lid of the RTL control module recognized from the value of the trunk lid/tailgate opening angle recognition sensor (B24/16).

5. The RTL control module (N121) actuates the motor of the trunk lid power locking motor (6) until the striker eye is in the bottom end position, which is recognized by the power locking switch (S88/14).

If the remote control key (A8/1) is pressed again, the opening procedure is stopped. It can be continued by pressing again. It is not  possible to "close" with the remote control key (A8/1) due to safety reasons.

Lock-up recognition: 

Lock-up is recognized if the value of the trunk lid/tailgate opening angle recognition sensor (B24/16) does not change during actuation of the trunk lid drive motor (M15/2).

• If lock-up is recognized during closing, the trunk lid drive motor (M15/2) is actuated and the trunk lid is moved back to its initial position.
• If a lock-up is recognized during opening, the trunk lid drive motor (M15/2) is switched off, the trunk lid remains in its momentary position.