Temperature Control

Component Identification:

Function
The electronically controlled refrigeration, heating and ventilation system for automatic air conditioning or rear air conditioning reaches the desired passenger compartment temperature as quickly as possible or holds it constant by

- Cooling the air in the evaporator
- Heating the air in the heater core

- Heating mode
The heat exchanger temperature sensors (B10/2 and B10/3) measure the air temperature at the heater core while the in-car temperature sensors (N22b1 and N70b1) measure the associated temperature in the passenger compartment.
In addition the outdoor temperature is measured by the outdoor temperature sensor (B14) and the intensity and direction of the sun radiation by the sun sensor (B32/2).
The electronic circuitry in the automatic A/C pushbutton control module (N22) compares the various values with the temperature set with the temperature buttons.
The electronic circuitry regulates the automatic air conditioning as required by actuating the duovalves or maintaining the present setting.

- Air conditioning mode
The evaporator temperature sensor (B10/6) measures the air temperature at the evaporator air outlet while the in car-temperature sensors (N22b1 and N70b1) measure the associated temperature in the passenger compartment.
In addition the outdoor temperature is measured by the outdoor temperature sensor (B14) and the intensity and direction of the sun radiation by the sun sensor (B32/2).
The electronic circuitry in the automatic A/C pushbutton control module (N22) compares the various values with the temperature set with the temperature buttons.
The electronic circuitry regulates the automatic air conditioning as required by actuating the A/C compressor or maintaining the present setting.
On vehicles with rear air conditioning (code 582)

- Heating mode.
The heat exchanger temperature sensors measure the air temperature at the rear heater core. The electronic circuitry in the automatic A/C pushbutton control module compares the reading with the temperature set with the temperature buttons.
The electronic circuitry regulates the rear air conditioning as required by actuating the duovalves or maintaining the present setting.

- Air conditioning mode
The evaporator temperature sensor measures the air temperature at the rear evaporator air outlet. The electronic circuitry in the rear A/C pushbutton control module compares the various values with the temperature set with the temperature buttons.
The electronic circuitry regulates the rear air conditioning as required by actuating the refrigerant shutoff or maintaining the present setting.