GF83.20-P-2120-02SK Heating Pushbutton Control Unit, Task

GF83.20-P-2120-02SK Heating Pushbutton Control Unit, Task
- except CODE (580) Automatic air conditioning
- except CODE (581) Comfort automatic air conditioning

Component Identification:

Task
The HEAT control and operating unit (N18) controls all the functions for ventilating and heating the vehicle interior.

The HEAT control and operating unit (N18) is used to control the following:
^ Interior temperature selection, separate for driver and passenger
^ Manual blower control
^ Manual air distribution
^ Recirculated air mode
^ Activation of residual engine heat utilization with ignition switched off
^ Defrost function
^ Rear window heater

The HEAT control and operating unit (N18) actuates the following:
^ Directly: the duovalve
^ Via the AC bus: the blower regulator, the fresh air and recirculated air flaps actuator motor, the left and right footwell flaps actuator motor and the left and right defroster flaps actuator motor

The following signals are read in directly by the HEAT control and operating unit (N18):
^ the left heat exchanger temperature sensor and the right heat exchanger temperature sensor

Illustration of individual operating facilities

Temperature selector wheel, left (1) and right (4)
The left (1) and right (4) temperature selector wheels can be used to manually select and display the interior temperature at the driver and front passenger sides:
^ by rotating the left temperature selector wheel (1) around the recirculated air switch (N18s2) for the driver-side
^ by rotating the right temperature selector wheel (4) around the heated rear window switch (N18s1) for the front passenger side
^ the indication by the respective LED ring

Blower control switch (2) and air distribution switch (3)
The blower control switch (2) and the air distribution switch (3) are used for manual selection and display of the air distribution and blower capacity:
^ by rotating the blower control switch (2) around the residual heat button (5)
^ by rotating the air distribution switch (3) around the defrost button (6)
^ the indication by the respective LED ring

Residual heat button (5)
Heating or ventilation can be provided for up to 30 minutes by pressing the residual heat button (5). The function is only possible with circuit 15 off or circuit 15C on. If there is low voltage, the residual heat function is automatically switched off.

Defrost button (6)
Pressing the defrost button (6) sets the temperature to "maximum" and distributes the air flow to the defrosting and lateral nozzles. All the other flaps are closed. The blower voltage is controlled depending on the coolant temperature.

Recirculated air switch (N18s2)
Briefly pressing the recirculated air switch (N18s2) for less than 1.5 seconds closes the recirculated air flap to prevent air from being led in from the outside. The function LED is illuminated during operation.The function is deactivated if the Vario roof is open. Pressing the switch for longer activates the power window comfort opening/closing facility.

Heated rear window switch (N18s1)
When the rear window heater switch (N18s1) is pressed, the HEAT control and operating unit (N18) transmits a switch-on request to the rear SAM control unit with fuse and relay module via the class B Controller Area Network bus (interior) (CAN-B), which switches on the rear window heater and the function LED at the same time.