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Engine start/stop, function - GF80.61-P-3012SX

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

Fig 1: Engine Start/Stop Function Diagram
G07590920Courtesy of MERCEDES-BENZ USA

Shown on model 221 

Function 

The engine or circuits 15C, 15R, 15 can be switched on or switched off by pressing the start/stop button on the EIS control unit.

Start engine, function 

Function requirements 

Function 

When the start/stop button in the EIS control unit is pressed, a request is transmitted to the Keyless Go control unit. It then transmits locating signals via the center console Keyless Go antenna and the interior Keyless Go antenna to allow the transmitter key to determine its position.

Simultaneously with this procedure, the Keyless Go control unit requests the transmitter key to transmits an access authorization code.

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 sent to the EIS control unit via the interior CAN. If valid, circuit 15R and circuit 15 are switched on and the engine is started.

Possible error messages in the instrument cluster if function prerequisites are not fulfilled 

"To start. Select drive position P or N".

Activating c.15C, 15R or 15 without engine start 

If the foot brake is not depressed when the start/stop button is actuated, only circuit 15R is switched on. Repeated actuation activates circuit 15. Further repeated actuation switches circuit 15R and circuit 15 off. If the driver door is closed, c. 15C remains active for approx. 30 minutes.

Shut off engine, function 

The engine can be switched off any time via the start/stop button

Function 

The signal "Switch off engine" is transmitted to the EIS control unit by pressing the start/stop button and then the engine is switched off via circuit 15. With the driver door closed, circuit 15C remains active for approx. 30 minutes.

Switch-off function of engine depending on vehicle speed 

Starting requests, function 

Each time the vehicle is started or if a door is opened with the engine running, the EIS control unit requests the Keyless Go control unit to check the transmitter key.

If a transmitter key is not recognized in the passenger compartment, the instrument cluster indicates: "Key not recognized".

  Rear window antenna module, component description A2/12
Vehicles with/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 
  CDI control unit, component description N3/9
Model 221 with engine 642
GF07.16-P-6000SX
  ME-SFI [ME] control unit, component description N3/10
Model 221 with engine 272.965, 273.961
Model 216 with engine 273.961
GF07.61-P-6000V
  ME-SFI control unit, location/task/design/function N3/10
Model 221 with engine 275.953/982
GF07.61-P-5000M
  ESP control unit, component description N47-5 GF42.45-P-5118SX
  Keyless Go control unit, component description N69/5 GF80.61-P-4200SX 
  Electronic ignition/starter switch control unit (EIS), component description N73 GF80.57-P-6000SX 
  Central gateway control unit, component description N93 GF54.21-P-4170SX