Electric seat ventilation, function - GF91.30-P-0002G

MODEL 463.306 /336 /346 up to 31.5.12 with CODE (S50) Seat ventilation for driver and front passenger seat as of Model Year 2011/ YoM 10 

MODEL 463.202 /222 /236 /237 /270 /271 /303 /340 /341 up to 31.5.12 with CODE (S50) Seat ventilation for driver and front passenger seat as of Model Year 2009/ YoM 08 

Function requirements, general 

• Circuit 15R On

Seat ventilation, general 

The seat cushions and backrests of the front seats can be ventilated in three stages using the seat ventilation.

The seat ventilation consists of the following subfunctions:

• Ventilation mode function sequence 
• End ventilation mode function sequence 

Ventilation mode function sequence 

The left front seat ventilation switch or the right front seat ventilation switch in the upper control panel control unit are used to switch the seat ventilation of the driver and front passenger seat on and off and regulate the ventilating power. The feedback of the configured ventilating power is provided via three light-emitting diodes (LED) in the corresponding front seat ventilation switch.

The specified value for the corresponding ventilation stage is transmitted by the upper control panel control unit to the blower regulators. They then provide the corresponding voltage to the motor groups. Pressing the seat ventilation switch one time activates stage 3 of the seat ventilation (three LEDs come on). When the corresponding seat ventilation switch is pressed again, the system switches to stage 2 (two LEDs come on).

When the corresponding seat ventilation switch is pressed once more, the system switches to stage 1 (one LED comes on).

Switching the seat ventilation on, over or off by operating the left/right front seat ventilation switch is possible at any given time.

During comfort opening with the transmitter key (A8/1) (infrared signal), the seat ventilation of the driver seat is switched on in stage 3 for t = 5 min. When the front seat ventilation switch is pressed one time with circuit 15R Off, the seat ventilation is then switched off again before the cut-in time has elapsed.

End ventilation mode function sequence 

The "End ventilation mode function" is split up into the following partial functions:

• Function sequence for manual seat ventilation cutout 
• Function sequence for shutting off after circuit 15R Off 
• Function sequence for shutting off in the event of undervoltage 
• Function sequence for shutting off during the starting procedure 

Function sequence for manual seat ventilation cutout 

The seat ventilation can be switched off manually by pressing the left front seat ventilation switch or the right front seat ventilation switch; all LEDs in the left front seat ventilation switch or right front seat ventilation switch must have gone out.

Function sequence for shutting off after circuit 15R Off 

After cutting out circuit 15R, the seat ventilation is cut out as well (load output and function indicator). However, the internal timer control continues running for t = 5 minutes, while circuit 15C is ON.

If circuit 15R is switched on again, then the seat ventilation is also switched on again in accordance with the timer control stage.

Function sequence for shutting off in the event of undervoltage 

When falling below the undervoltage threshold, the seat ventilation (only load output) is cut out. It can only be cut in again, after a permissible voltage was present for t = 20 seconds. When undervoltage is detected, the LEDs of the left front seat ventilation switch or right front seat ventilation switch that are active in each case are flashing synchronously with approx. f = 1.5 Hz.

If overvoltage is recognized, the seat ventilation is not cut out. If an output short circuit is present, the upper control panel control unit stores no error in the fault memory.

Function sequence for shutting off during the starting procedure 

During the starting procedure the seat ventilation (only load output) is cut out. However, the internal timer control continues running for t = 5 minutes during the starting procedure. The same timer control is active during an aborted starting procedure.

After the starting procedure has taken place, the seat ventilation is switched on again with a delay of t = 2 s in accordance with the stage that is active. The status of the function indicator remains set during the starting procedure.

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	Electrical seat ventilation block diagram		GF91.30-P-0002-03G
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