Switching off Airscarf system, function - GF91.30-P-2011SK

MODEL 171.4 with CODE (403) AIRSCARF system 

Switching off manually 

The Airscarf system is switched off manually by pressing the left AIRSCARF switch (N72/1s21) or the right AIRSCARF switch (N72/1s22).

Depending on the active heating stage, it may be necessary to press the left AIRSCARF switch (N72/1s21) or the right AIRSCARF switch (N72/1s22) repeatedly.

To protect the left head area ventilation heating element (R22/5) or the right head area ventilation heating element (R22/6) from overheating, the left head area ventilation fan (M4/10) or the right head area ventilation fan (M4/11) is actuated for 10 s at the lowest stage by the front HS [SIH], head area ventilation and steering wheel heater control unit (N25/7).

Switching off automatically 

If one of the following criteria occurs, the Airscarf system shuts off. The criteria are listed in the order of decreasing priority.

• Switching off in the event of a hardware defect 

  If an actuation of the left head area ventilation heating element (R22/5) or the right head area ventilation heating element (R22/6) is detected without a current request or function prerequisite being present, then the Airscarf system is shut off and a fault is stored in the fault memory.

• Switching off in the event of a defective left head area ventilation fan (M4/10) or right head area ventilation fan (M4/11) 

  If, in the event of an active heating stage, it is detected by the front HS [SIH], head area ventilation and steering wheel heater control unit (N25/7) that the square-wave signal of the left head area ventilation fan (M4/10) or right head area ventilation fan (M4/11) is missing, the Airscarf system is shut off and a fault is stored in the fault memory.

• Switching off with excessively high temperature 

  If the left head area ventilation thermostat (B10/27) or the right head area ventilation thermostat (B10/28) detects an excessively high temperature, the Airscarf system is shut off. Automatic switching back on again does not occur.

• Switching off as under terminal 15R OFF 

  When switching off circuit 15R, the Airscarf system is switched off. However, the timer control continues to run for 5 min., as long as circuit 15C is On. If within this time period circuit 15R or circuit 15 is switched on again, then the Airscarf system is also switched to the state that was active last.

• Switching off in the event of undervoltage 

  If the voltage drops below the undervoltage threshold (11.0 V ± 0.5 V) then the left head area ventilation heating element (R22/5) or the right head area ventilation heating element (R22/6) as well as the left head area ventilation fan (M4/10) or the right head area ventilation fan (M4/11) are shut off.

  The active LEDs in the function indicator then flash on and off at approx. 1.5 Hz and 50% brightness. It is not possible to switch on again manually until a permissible voltage is present again for 5 s.

• Switching off in the event of overvoltage 

  If the voltage exceeds the overvoltage threshold (15.5 V ± 0.5 V) then the left head area ventilation heating element (R22/5) or the right head area ventilation heating element (R22/6) as well as the left head area ventilation fan (M4/10) or the right head area ventilation fan (M4/11) are shut off. The function indicator remains set for the selected heating stage. It is not possible to switch on again manually until a permissible voltage is present again.

• Switching off during starting procedure 

  During the starting procedure, the left head area ventilation heating element (R22/5) or the right head area ventilation heating element (R22/6) as well as the left head area ventilation fan (M4/10) or the right head area ventilation fan (M4/11) are shut off.

  The function indicator during this time remains set for the selected heating stage.