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Locking/unlocking, function - GF80.61-P-2008SX

MODEL 221.0 /1, 216.3 with CODE (889) Keyless Go up to Model Year 8 

Fig 1: Keyless Go Locking/Unlocking Function Diagram
G07590919Courtesy of MERCEDES-BENZ USA

Shown on model 221 

Unlocking/locking function via door handle 

Function requirements 

Unlocking possibilities: 

Locking possibilities: 

Function sequence for unlocking 

(Explained on left front door on model 221 as an example)

The inner capacitive sensor in the left front Keyless Go sensor unit recognizes if a door handle is gripped and signals this to the Keyless Go control unit which transmits a wake-up signal to the transmitter key via the left rear door Keyless Go antenna.

The transmitter key transmits its access authorization code and its position to the rear window antenna amplifier module, which relays it to the Keyless Go control unit. The access authorization code is transmitted to the EIS control unit via the interior CAN. If it is valid, the EIS control unit transmits the command "Unlock CL" to the door control units and to the rear SAM control unit. They actuate the corresponding motors in the central locking (CL) to unlock. If a door handle is pulled within 0.5 s after the CL is unlocked, the Hall sensor in the door handle senses this and sends a corresponding signal to the Keyless Go control unit, which then actuates the left front opening assist motor. When the left front opening assist motor is actuated, the rotary tumbler "Opens" and the door pops open.

Function sequence for locking 

(Explained on left front door on model 221 as an example)

The outer capacitive sensor in the left front Keyless Go sensor unit recognizes if a door handle is gripped from the outside. Further sequence same as when unlocking, however, the CL motors are actuated to lock.

IMPORTANT The convenience closing function via Keyless Go (KG) is described in the "Convenience feature function".

Switching over from "global" to "selective" unlocking. 

If the unlock and lock buttons on the transmitter key are pressed simultaneously for 5 seconds, a change between the "global" and "selective" functions takes place. The indicator lamp on the transmitter key comes on to confirm this change.

Only the driver door and the fuel filler flap can be unlocked by gripping and pulling the driver door handle. If, however, the transmitter key is set to selective unlocking and the triggering location for unlocking is not the driver door handle, the vehicle is unlocked globally.

Unlocking function via trunk lid external operation switch 

Function sequence 

The rear SAM control unit recognizes when the trunk lid external operation switch is actuated and signals it to the KEYLESS-GO control unit via interior CAN.

It transmits a wake-up signal to the transmitter key via the left trunk Keyless Go antenna.

The transmitter key transmits its access authorization code and its position to the rear window antenna amplifier module, which relays it to the Keyless Go control unit.

The access authorization code is transmitted to the EIS control unit via the interior CAN. If it is valid, the EIS control unit sends the command "Unlock CL" to the rear SAM control unit, which actuates the trunk lid CL motor and opens the rotary tumbler.

IMPORTANT On vehicles with code (881) Remote trunk closing (RTC) the automatic mode is stopped when the trunk lid external operation switch is actuated again; if actuated anew, the procedure is continued.

Locking function via trunk lid KG button 

(Model 221 up to 30.11.06) 

Function requirements 

Function sequence 

If the trunk lid Keyless Go button is pressed, this is recognized by the rear SAM control unit and relayed to the Keyless Go control unit. It transmits a wake-up signal to the transmitter key via the left trunk Keyless Go antenna.

The transmitter key transmits its access authorization code and its position to the rear window antenna amplifier module, which relays it to the Keyless Go control unit. The access authorization code is transmitted to the EIS control unit via the interior CAN.

If it is valid, the EIS control unit transmits the command "Lock CL" to the door control units and the rear SAM control unit. They then actuate the corresponding CL motors to lock.

The function is accomplished regardless of whether the trunk lid is open or closed.

Locking function via RTC button (with code (881) Remote trunk closing (RTC)) 

If the TLC button is actuated when the trunk lid is open, a signal is transmitted from the TLC control unit to the KEYLESS-GO control unit via the interior CAN.

It transmits a wake-up signal to the transmitter key via the left trunk Keyless Go antenna.

The transmitter key transmits its access authorization code and its position to the rear window antenna amplifier module, which relays it to the Keyless Go control unit.

The access authorization code is transmitted to the EIS control unit via the interior CAN. If it is valid, the EIS control unit sends the command to lock the vehicle and the command to release the trunk lid lock. The TLC control unit closes the trunk lid.

  Rear window antenna module, component description A2/12
Vehicles without code (494) USA version or without code (498) Japan version
GF82.62-P-3131SX
Vehicles with code (498) Japan version GF82.62-P-3131SXJ
Vehicles with code (494) USA version GF82.62-P-3131SXU
  Keyless Go antenna, component description A2/35, A2/39, A2/41, A2/60, A2/61 GF82.62-P-4099SX
  Transmitter key, component description A8/1 GF80.57-P-6010SX 
  Keyless Go sensor unit, component description B67/1, B67/2, B67/3, B67/4 GF80.61-P-4109SX 
  Rear SAM control unit with fuse and relay module, component description N10/2 GF54.21-P-6030SX
  Driver-side front door control unit, component description N69/1
Model 221
GF72.29-P-6000SX
Model 216 GF72.29-P-6000SC
  Passenger-side front door control unit, component description N69/2
Model 221
GF72.29-P-6010SX
Model 216 GF72.29-P-6010SC
  Rear door control unit, component description N69/3, N69/4
Model 221
GF72.29-P-6020SX
  Keyless Go control unit, component description N69/5 GF80.61-P-4200SX 
  Electronic ignition switch control unit (EIS), component description N73 GF80.57-P-6000SX 
  TLC control unit, component description N121
Vehicles with code (881) Remote trunk closing (RTC)
GF80.20-P-6000SX 
  Trunk lid Keyless Go button, component description S62/21
Model 221 up to 30.11.06
GF80.61-P-4107SX 
  Close TLC button and lock Keyless Go, component description S62/26
Vehicles with code (881) Remote trunk closing (RTC)
GF80.61-P-4108SX