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

MODEL 216.3, 221.0 /1 with CODE (889) KEYLESS-GO as of model year 2009 /YoM 08 

Function requirements, general 

Engine start/stop, general 

The engine start/stop function allows to start and stop the engine.

The engine start/stop function comprises the following subfunctions.

Additional function requirements for starting engine 

Function sequence for starting engine 

After pressing the KEYLESS-GO start/stop button (S2/3) the EIS control unit (N73) transmits the request for an access authorization code and transmits the signal "Start engine" to the KEYLESS-GO control unit (N69/5) via the interior CAN (CAN B). The KEYLESS-GO control unit causes the following antennas to transmit a wake-up and location finding signal to the transmitter key:

The transmitter key transmits its access authorization code and its position to the rear window antenna amplifier module (A2/12), 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 the access authorization code is valid and the transmitter key is located in the vehicle interior, c. 15R and c. 15 are switched on and the motor for the ME-SFI control unit (N3/10) (on gasoline engine) or CDI control unit (N3/9) (on diesel engine) is started.

Error messages in instrument cluster (A1):

If a transmitter key is not recognized in the interior compartment when starting, the instrument cluster indicates "Key not recognized" and the start attempt is interrupted (circuit 15R and circuit 15 remain off).

IMPORTANT The display request in the instrument cluster is transmitted by the EIS control unit to the central gateway control unit (N93) via the interior CAN. The central gateway control unit routes this request to the instrument cluster via the central CAN (CAN F).

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 then a transmitter key is not recognized in the passenger compartment, the instrument cluster displays the message "Key not recognized" in red and a warning tone is output via the warning buzzer (A1h1).

Function sequence for circuit activation 

If the foot brake is not depressed when the KEYLESS-GO 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, circuit 15C remains active for t = 30 min.

Function sequence for stopping engine 

When the KEYLESS-GO start/stop button is pressed, the signal "Stop engine" is transmitted to the EIS control unit and then c. 15 is switched off and the motor is switched off by the ME-SFI control unit or CDI control unit. If the driver door is closed, circuit 15R remains active for t = 30 min.

IMPORTANT Switching off engine depending on vehicle speed:

REFER TO SYSTEM WIRING DIAGRAMS Function schematic for electric KEYLESS-GO engine start/stop Model 216 PE80.61-P-2052-97CAA
Model 221 PE80.61-P-2052-97SAA
  Component description for instrument cluster A1
Model 216.3, model 221 (except 221.095/195)
GF54.30-P-6000LE
Model 221.095/195 GF54.30-P-6000LEH
  Component description for CDI control unit N3/9
Model 221 with engine 629.9
GF07.16-P-6000OA
Model 221 with engine 642.8 GF07.16-P-6000OHS
Model 221 with engine 642.9 GF07.16-P-6000OHL
  Component description for ME-SFI [ME] control unit N3/10
With engine 156
GF07.61-P-6000MAS
On model 221 with engine 272 (except 272.974) GF07.61-P-6000MIS
Model 221 with engine 272.974 GF07.61-P-6000MEH
With engine 273 GF07.61-P-6000MLS
With engine 275 GF07.61-P-6000MOS
Model 221 with engine 276 GF07.61-P-6000MMB
On engine 157, 278. GF07.61-P-6000MMC
  Component description for regenerative braking system control unit N30/6
On model 221.095/195
GF42.22-P-1100LEH
  Component description for ESP control unit N47-5
Model 216.3, 221 (except 221.095/195)
GF42.45-P-5118LE
  Component description for KEYLESS-GO control unit N69/5 GF80.61-P-4204LE 
  EZS control unit, component description N73 GF80.57-P-6003LE 
  Component description for central gateway control unit N93 GF54.21-P-4170LE