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GF83.40-P-3000CAA Component Description For Automatic Air Conditioning Control and Operating Unit



GF83.40-P-3000CAA Component Description For Automatic Air Conditioning Control And Operating Unit
- except CODE (581) Comfort automatic air conditioning


Component Identification:





Component Identification:






Location
The control and operating unit is located in the instrument panel.

Design
The control and operating unit contains the following controls and displays:
- Defroster button
- "ZONE" button
- "AUTO" button
- "A/C" button
- "OFF" button
- Display
- Right temperature rocker
- Air volume rocker
- Air distribution rocker
- Left temperature rocker
- "MAX COOL" button (with code (494) USA version)
- Rear window heater button
- Air recirculation mode button

Task
The control and operating unit has the following tasks:
^ Operation of the vehicle's climate control
^ Reading in of sensors and signals
^ Evaluation of input factors
^ Actuation of components

Operation of the vehicle's climate control
The control and operating unit enables the following operations:
- Interior temperature selection separated for the left and right side
- Automatic blower control and air distribution
- Manual blower control and air distribution
- Switch automatic air conditioning (AAC [KLA]) on and off
- Defrost function
- Switching the A/C compressor (A9) on and off
- Mono mode
- Recirculated air mode
- Maximum cooling output (with code (494) USA version)
- Control of the rear window heater (R1)

It is operated with the following buttons:
^ "OFF" button
^ Temperature rocker
^ Air volume rocker
^ Air distribution rocker
^ "AUTO" button
^ "A/C" button
^ Rear window heater button
^ "ZONE" button
^ Air recirculation mode button
^ Defrosting button
^ "MAX COOL" button (with code (494) USA version)

"OFF" button
The AAC [KLA] can be switched off completely or switched back on by pressing the "OFF" button.

Temperature rocker
Pressing the temperature rocker enables the required specified temperature to be set for the left and right sides. The temperature is shown on the display.
Maximum temperature setting: display "HI"; minimum temperature setting: display "LO".

Air volume rocker
The air volume can be adjusted manually by actuating the air volume rocker.
The selected setting is shown on the display.

Air distribution rocker
The air volume can be adjusted by actuating the air volume rocker.
The selected air distribution setting is shown on the display.

"AUTO" button
The air volume and the air distribution are regulated automatically when the AUTO button is pressed If automatic mode is activated, the LED lights up.

"A/C" button
Pressing the "A/C" button switches the refrigerant compressor on or off with "circuit 61 ON". All other functions are retained.
The LED lights up when the refrigerant compressor is switched on.

Rear window heater button
The rear window heater is switched on when the rear window heater button is pressed. The LED lights up during operation.

The operating time of the rear window heater is calculated by the rear SAM control unit with fuse and relay module (N10/2) depending on the outside temperature, interior temperature and vehicle speed.

The detailed rear window heater procedure is described in the rear window heater (HHS) function.

"ZONE" button
When the"ZONE" button is pressed, the values for air distribution and temperature set on the driver side are adopted for the passenger side.
The LED goes out when the function is activated.
If the temperature on the passenger side is adjusted manually, the LED lights up. A multizone temperature control in the vehicle is thus shown.

Air recirculation mode button
By actuating the air recirculation mode button for t < 1.5 s the fresh air/recirculated air flap is closed to prevent air from flowing from outside. The air only circulates in the vehicle interior and unpleasant odors and harmful gases are kept out.
The LED for the air recirculation mode button lights up during operation.
Pressing the air recirculation mode button for t > 1.5 s activates comfort air recirculation closing. The windows and panoramic sliding roof (with code (413) Panoramic glass sunroof with top sliding sunroof) are closed.
When the air recirculation mode button is pressed again for t > 1.5 s, the windows and the panoramic sliding sunroof return to their previous positions.

The windows or the panoramic sliding sunroof, which were manually opened during the air recirculation phase, are not moved back to their previous positions once the air recirculation phase is over.

On vehicles with code (460) Canada version or code (494) USA version, comfort air recirculation closing is not possible.

The detailed comfort air recirculation closing procedure is described in the convenience feature (CF [KFB]) function.

Defrosting button
Pressing the defrosting button sets the temperature to "maximum" and distributes the air flow to the defroster vents. The fresh air/ recirculated air flap remains open. All other flaps of the air conditioner housing are closed. The blower output is regulated to match the coolant temperature. The LED lights up when the function is activated.

"MAX COOL" button (with code (494) USA version)
Pressing the "MAX COOL" button raises the basic ventilation level to 100 % and the "MAX COOL" indication appears in the display.

Reading in of sensors and signals
The input factors are read in via the following connections:
^ Direct line
^ Climate control LIN (LIN B8)
^ Interior CAN (CAN B)

Direct line
The following signals and sensors are read via a direct line:
- Interior temperature sensor (B10/4)
- Evaporator temperature sensor (B10/6)
- Left side air vent air outlet temperature sensor (B10/31)
- Right side air vent air outlet temperature sensor (B10/32)
- Left front footwell vent air outlet temperature sensor (B10/35)
- Right front footwell vent air outlet temperature sensor (B10/36)
- Sun sensor (B32/3)
- Interior temperature sensor with integrated fan (N70/3b1)

Climate control LIN
The following sensor is read in via climate control LIN:
- Interior humidity/temperature sensor (B82) (model 207.3 as of YoM 09/2 to 1.12.2009, model 207.4)

Interior CAN
The following signals are read in via interior CAN:
- Provided by instrument cluster (A1):
- Vehicle speed
- Provided by radio with auto pilot system (A2/56) (with code (511) Audio 50 APS with DVD changer) or by COMAND controller unit (A40/3) (with code (512) COMAND APS with DVD changer or with code (527) COMAND APS with single DVD drive (with navigation)):
- Status of voice control system (VCS)
- Provided by front SAM control unit with fuse and relay module (N10/1):
- Coolant temperature sensor (B11/4)
- Refrigerant pressure sensor (B12)
- Outside temperature sensor (B14)
- Engine speed
- Provided by electronic ignition lock control unit (N73):
- Status of circuit 15
- Provided by panoramic sliding sunroof control module (A98) (with code (413) Panoramic glass sunroof with top sliding sunroof):
- Position of the panoramic sliding sunroof

Evaluation of input factors
The input factors that have been read in are evaluated by the integrated microprocessor and the affected components are then actuated.

Actuation of components
The components are actuated via the following lines:
^ Direct line
^ Climate control LIN
^ Interior CAN

Direct line
The following component is actuated via a direct line:
- Blower regulator (A32n1)

Climate control LIN
The following components are actuated via climate control LIN:
- Fresh air/recirculated air flap actuator motor (M2/5)
- Left blend air flap actuator motor (M2/6)
- Right blend air flap actuator motor (M2/7)
- Defroster flap actuator motor (M2/16)
- Air distribution flap actuator motor (M16/22)
- PTC heater booster (R22/3) (with engine 271.8, 642.8 or 651.9)

Interior CAN
The following components are actuated via the interior CAN:
- From the rear SAM control unit with fuse and relay module:
- Refrigerant compressor control valve
- From the left front door control unit (N69/1):
- Left front door power window motor (M10/3)
- From the right front door control unit (N69/2):
- Right front door power window motor (M10/4)
- By the rear SAM control unit (N22/6):
- Left rear power window motor (M10/5)
- Right rear power window motor (M10/6)
- From the panoramic sliding sunroof control module (with code (413) Panoramic glass sunroof with top sliding sunroof):
- Panoramic sliding sunroof motor (A98m1)