Contents Wiring diagrams Section: Automatic HVAC System All sections

Climate Control -- Basic Knowledge -- 203 Chassis: Component Locations Mercedes-Benz C-class W203/S203/CL203

Automatic HVAC System 43 illustrations ~3876 words

Blower motor, location/task/function - GF83.10-P-2140P

MODEL 203

Locating Rear Blower Motor. Scheme 4

Scheme 2: Identifying Blower Motor
Blower, locationThe blower motor (A32m1) is located under the glove compartment on the right of the heating and evaporator housing.
Blower, taskIn normal operation the blower motor (A32m1) draws in fresh air via the fresh/recirculated air flap and in recirculated air operation it draws in air from the vehicle interior into the heating and evaporator housing.
In engine residual heat utilization operation the blower motor (A32m1) recirculates the air in the interior.
Blower functionGF83.10-P-2102-02P
On vehicles with Code 581a to 31.05.01 and Code 581b as of 01.06.01GF83.10-P-2102-02PC

Dust filter, location / task / function - GF83.10-P-2142P

MODEL 203

MODEL 209.3 /4 with CODE (581b) Convenience automatic air conditioning

Shown on model 203

Identifying Ventilation System, Air Inlet And Rear Vent. Scheme 5

Scheme 4: Identifying Dust Filter
Dust filter, positionThe dust filter (1) is located outside the heater and automatic AC housing upstream of the air inlet in the right rear of the water trough.
Dust filter taskThe dust filter (1) filters the fresh air drawn into the heater and automatic AC housing. The air drawn in from the vehicle interior in recirculation mode is not filtered.
Dust filter, functionThe filter element of the dust filter (1) consists of non-woven cloth which cleans the air flowing through. In the dust filter (1) over 80 % of particles of at least 0.3 μm in size are filtered out, 100 % as of 0.5 μm in size and pollen are filtered out

Multifunction sensor location/task/function - GF83.10-P-2148P

MODEL 203 up to 31.5.01 with CODE (581a) Air conditioning (Automatic)

MODEL 203 as of 1.6.01 with CODE (581b) Convenience automatic air conditioning

Function Of Heater Circuit. Scheme 6

Scheme 5: Locating C-AAC (K-KLA) Multifunction Sensor
Multifunction sensor, locationThe C-AAC [K-KLA] multifunction sensor (B31) is located in the fresh air inlet at the rear right of the engine compartment.
AAC multifunction sensor, taskThe C-AAC [K-KLA] multifunction sensor (B31) serves to record the following values: Ambient temperature air humidity pollutant concentrations of outside air
Multifunction sensor functionGF83.10-P-2135-02P

Rear blower motor, location/task/design/function - GF83.10-P-2168P

MODEL 203 as of 1.6.01

209.3 /4 with CODE (581b) Convenience automatic air conditioning

Shown on model 203

Scheme 4: Locating Rear Blower Motor
Rear blower motor, locationThe rear blower motor (M2/1) is located behind the rear nozzle below the center console.
Rear blower motor, taskThe rear blower motor (M2/1) serves to improve ventilation and cooling in the rear. The air which is drawn into the AC housing by the blower motor is led to the rear blower motor (M2/1) via air ducts.
Rear blower motor, functionModel 203GF83.10-P-2168-01P
Models 209.3/4GF83.10-P-2168-01Q

Control module for rear blower motor, location/task/design/function - GF83.10-P-2169P

MODEL 203 as of 1.6.01

209.3 /4 with CODE (581b) Convenience automatic air conditioning

Shown on model 203

Locating Rear Blower Motor And Rear Blower Motor Control Module. Scheme 7

Scheme 7: Locating Rear Blower Motor And Rear Blower Motor Control Module
Rear blower motor control module positionThe rear blower motor control module (N22/3) is located behind the rear nozzle below the center console.
Rear blower motor control module taskThe rear blower motor control module (N22/3) controls the rear blower motor (M2/1) voltage supply depending on the relevant blower level setting.
Blower motor control module, functionGF83.10-P-2169-01P

Air ducting, location/task/function - GF83.10-P-2182P

MODEL 203.0/ 2/ 7

Scheme 5: Identifying Ventilation System, Air Inlet And Rear Vent

Shown on model 203.0 up to 23.4.04 with code (581) automatic air conditioning

Air ducting, location See figure. Air ducting, task GF83.10-P-2182-01P Air ducting, function GF83.10-P-2182-02P

Heater housing, location/task/design/function - GF83.20-P-2103P

MODEL 203.0 /2 /7 up to 23.4.04 except CODE (580) Air conditioning (or Tempmatic for USA) except CODE (580) Automatic air conditioning except CODE (581) Automatic air conditioning except CODE (581) Comfort automatic air conditioning

Identifying Heater Housing. Scheme 8

Scheme 8: Identifying Heater Housing
Heater housing positionThe heater housing (1) is located beneath the instrument panel.
Heater housing taskGF83.20-P-2103-03P
Heater box designGF83.20-P-2103-04P
Heater box functionGF83.20-P-2103-02P

Heating system heat exchanger, location/task/function - GF83.20-P-2108P

MODELS 203, 209.3 /4

Identifying Heating System Heat Exchanger. Scheme 9

Scheme 9: Identifying Heating System Heat Exchanger
Heating system heat exchanger, locationThe heater heat exchanger (1) is located behind the instrument panel in the heater/AC housing.
Heating system heat exchanger, taskThe heater heat exchanger (1) is used to heat up the air flow which is led to the vehicle interior via the various defroster nozzles, ventilation and heating nozzles.
Heating system heat exchanger functionGF83.20-P-2101-01P

Heating water circulation pump, location/task/function - GF83.20-P-2109P

MODEL 203.0 /2 /7 up to 31.5.01 with CODE (581a) Air conditioning (Automatic)

MODEL 203.0 /2 /7 as of 1.6.01 with CODE (581b) Convenience automatic air conditioning

MODEL 203.0 /2 /7 with CODE (450) Taxi version with CODE (670a) Residual engine heat utilization (REST)

MODEL 209.3 with CODE (670a) Residual engine heat utilization (REST) except CODE (581b) Convenience automatic air conditioning

MODEL 209.3 with CODE (581b) Convenience automatic air conditioning

MODEL 209.4 with CODE (670a) Residual engine heat utilization (REST) except CODE (581b) Convenience automatic air conditioning

MODEL 209.4 with CODE (581b) Convenience automatic air conditioning

Shown on model 203

Identifying Hot-Water Recirculation Pump. Scheme 10

Scheme 10: Identifying Hot-Water Recirculation Pump
Coolant circulation pump, positionThe heating water circulation pump (M13) is located at the right front in the engine compartment next to the coolant compensating reservoir.
Heating water circulation pump taskThe heater water circulation pump (M13) serves to maintain a constant flow of hot water through the heat exchanger in the event of low engine speeds and residual engine heat utilization.
Heating water circulation pump functionAn electric motor drives the contactless impeller in an encapsulated housing via a magnetic driver.

Identifying Heating Push-Button Control Unit. Scheme 11

Scheme 11: Identifying Heating Push-Button Control Unit

The following settings can be performed on the HEAT [HAU] control and operating unit (N18)

  1. Interior temperature using the left temperature selector wheel (2) or right temperature selector wheel (3)
  2. Air volume using the blower switch (1)
  3. Air distribution using the air distribution switch (4)
  4. Air recirculation mode by pressing the air recirculation switch (N18s2)
  5. Defrost function by pressing the defroster button (5)
  6. Control of the heated rear window by pressing the heated rear window switch (N18s1)

The HEAT control and operating unit (N18) has diagnostic capability. As a result, any faults which occur are stored in a fault memory which can be read out using STAR DIAGNOSIS.

The HEAT [HAU] control and operating unit (N18) controls all actuators of the automatic heater (HEAT [HAU]).

The HEAT control and operating unit (N18) reads in the following signals via the Controller Area Network bus class B (interior) (CAN-B)

  1. ambient air temperature sensor
  2. in-car temperature sensor (up to 31.5.02) via the overhead control panel control unit
  3. battery voltage, coolant temperature sensor and engine speed via the EIS [EZS] control unit
  4. ground speed via the instrument cluster

The interior temperature of vehicles as of 1.6.02 is measured exclusively by the in-car temperature sensor integrated in the HEAT [HAU] control and operating unit (N18)

Blower switch (1)

The blower switch (1) controls the output of the blower motor. The blower switch (1) switches the control voltage for the blower regulator in 6 stages and 4 intermediate positions via the HEAT [HAU] control and operating unit (N18). As a result, a blower speed of 0 - 100 % is achieved.

Left temperature selector wheel (2) and right temperature selector wheel (3)

The left temperature selector wheel (2) and the right temperature selector wheel (3) serve to preselect the desired interior temperature. By turning it, the desired interior temperature is set separately for the left and right sides. The HEAT [HAU] control and operating unit (N18) compares the desired temperature with the current interior temperature which is measured by the in-car temperature sensor (up to 31.5.01) in the overhead control panel control unit.

Based on the comparison between specified and actual values, the HEAT [HAU] control and operating unit (N18) determines the correct position of the blend air flaps and actuates them separately.

The selected temperature is reached and maintained as quickly as possible if warming or cooling of the interior is required.

Air distribution switch (4)

The air distribution switch (4) controls the air flow to the air outlets for ventilation of the passenger compartment.

The air distribution can be set manually by turning the air distribution switch (4).

By turning the air distribution switch (4) on the HEAT [HAU] control and operating unit (N18), the left blend air flap actuator motor, the right blend air flap actuator motor, the left and right footwell flaps actuator motor, the left and right defroster flaps actuator motor, and the fresh air flaps actuator motor are actuated via the AC bus. Apart from the 4 basic settings, additional 8 intermediate settings can be selected.

Defroster button (5)

Pressing the defroster button (5) initiates the defrost function.

The defroster function works according to the following new logic

  1. heating power is controlled by the outside temperature.
  2. the entire air flow is directed towards the windshield and front side windows, defroster outlets opened
  3. blend air flaps controlled
  4. footwell vents closed
  5. blower power at 80 %, can be manually controlled

Air recirculation switch (N18s2)

The air recirculation switch (N18s2) is used to operate the fresh air/air recirculation flap in order to enable air supply from the vehicle interior.

Briefly pressing the air recirculation switch (N18s2) for < 1.5 s actuates the fresh air/air recirculation flaps actuator motor which actuates the fresh air/air recirculation flap, which in turn closes the fresh air duct and opens the recirculated air duct to enable air to be supplied from the vehicle interior. The LED in the air recirculation switch (N18s2) is on during air recirculation mode.

Recirculation air convenience closing function

If the air recirculation switch (N18s2) is pressed for longer than 1.5 s, all open windows and the tilting/sliding roof (SHD) (with code (414) Power glass tilting/sliding roof) are closed in automatic mode (windows and tilting/sliding roof (SHD) must be normalized) in addition to activation of the recirculated air function. The LED in the air recirculation switch (N18s2) is on during air recirculation mode. The tilting/sliding roof (SHD) and the power windows are actuated subsequently to prevent current peaks.

If the button is pressed once again for > 1.5 s, the windows and the tilting/sliding roof (SHD) move back to the previously stored positions and the fresh air/air recirculation flap moves to the fresh air position (LED off).

The convenience closing function can only be started if the LED in the air recirculation switch (N18s2) is not illuminated.

Any window which has been opened manually during air recirculation mode remains in this position when the recirculation air function is canceled; all other windows move to the stored positions. The positions of the tilting/sliding roof (SHD) and of the windows prior to the commencement of the closing operation are stored by the overhead control panel control unit or by the door control units. The windows and the tilting/sliding roof (SHD) which were closed using the convenience locking function remain closed when the air recirculation switch (N18s2) is pressed for < 1.5 s. In this case only the fresh air/ recirculated air flap is moved into the fresh air position. The stored positions are canceled when the ignition is switched off.

REST button (with code (450) Taxi version or code (670) Residual engine heat utilization system (REST [MRA]))

When the REST button (which is combined with the air recirculation switch (N18s2)) is pressed, the residual engine heat utilization system is switched on. When the engine is switched off, the residual heat heats the vehicle interior as a function of the temperature set on the HEAT [HAU] control and operating unit (N18) and of the ambient temperature. The vehicle can be heated for approx. 30 minutes with the engine switched off. The function is only available when the ignition is switched off or when the transmitter key in the EIS [EZS] control unit is in position 1. The residual engine heat utilization system is switched off automatically in the event of undervoltage. The flaps for the air distribution and the air volume are regulated automatically.

The residual heat function is switched off under the following conditions

  1. Transmitter key in position 2
  2. Approx. 30 min have elapsed
  3. Battery voltage drop below 11 V

Heating push-button control unit, location/task - GF83.20-P-2120PP

MODEL 203.0 /2 /7 up to 23.4.04 except CODE (580) Air conditioning (or Tempmatic for USA) except CODE (580) Automatic air conditioning except CODE (581) Automatic air conditioning except CODE (581) Comfort automatic air conditioning

Automatic Air Conditioning (AAC) Component Networking - Comfort Closing And Opening. Scheme 12

Scheme 20: Identifying HEAT (HAU) Control And Operating Unit
Heating push-button control unit, locationThe HEAT control and operating unit (N18) is in the center console.
Heating push-button control unit, taskGF83.20-P-2120-02PP

Automatic heater actuator motors location/task/function - GF83.25-P-2180P

MODEL 203.0 /2 /7 up to 23.4.04 except CODE (580) Air conditioning (or Tempmatic for USA) except CODE (580) Automatic air conditioning except CODE (581) Automatic air conditioning except CODE (581) Comfort automatic air conditioning

Identifying Fresh Air/Air Recirculation Flaps Actuator Motor And Left Blending Air Flap Actuator. Scheme 13

Scheme 13: Identifying Fresh Air/Air Recirculation Flaps Actuator Motor And Left Blending Air Flap Actuator
Automatic heater actuator motors locationThe actuator motors (M2/5, M2/6, M2/7, M2/15, M2/16, M2/21) are on the heater housing.
Automatic heater actuator motor taskGF83.25-P-2180-01P
Automatic heater actuator motor functionGF83.25-P-2180-02P

Activated carbon filter, location/task/function - GF83.30-P-2118P

MODEL 203 up to 31.5.01 with CODE (581a) Air conditioning (Automatic)

MODEL 203 as of 1.6.01 with CODE (581b) Convenience automatic air conditioning

MODEL 209.3 /4 with CODE (581b) Convenience automatic air conditioning

Shown on model 203

Locating Activated Charcoal Filter. Scheme 14

Scheme 14: Locating Activated Charcoal Filter
Activated charcoal filter, locationThe activated charcoal filters (1) are located in the comfort automatic air conditioning housing behind the instrument panel.
Activated charcoal filter, taskThe activated charcoal filter (1) serves to reduce the level of pollutants and odors in the intake air.
Activated charcoal filter, functionGF83.30-P-2113-02P

Air humidity sensor, location/task/design/function - GF83.30-P-2125P

MODEL 203.0 /2 /7 up to 31.5.01 with CODE (580) Air conditioning (or Tempmatic for USA)

MODEL 203.0 /2 /7 as of 1.6.01 with CODE (580) Automatic air conditioning

MODEL 203.0 /2 /7 as of 24.4.04 up to 28.6.06 except CODE (581) Comfort automatic air conditioning

Shown on model 203.0

Identifying Air Humidity Sensor. Scheme 15

Scheme 15: Identifying Air Humidity Sensor
Air humidity sensor, positionThe air humidity sensor (B31/2) is located in the air flow upstream of the fresh air/air recirculation flap at the automatic air conditioning box.
Air humidity sensor, taskThe air humidity sensor (B31/2) detects the air humidity.
Air humidity sensor, designThe air humidity sensor (B31/2) basically consists of the following parts: Measuring cell for humidity Electrical connector (3-pin) Electronic printed circuit board with processor Plastic housing, watertight with sensor orifice
Air humidity sensor, functionGF83.30-P-2125-01P

Air conditioner housing, location/task/design/function - GF83.40-P-2105P

MODEL 203.0 /2 /7 up to 31.5.01 with CODE (580) Air conditioning (or Tempmatic for USA)

MODEL 203.0 /2 /7 as of 1.6.01 with CODE (580) Automatic air conditioning

MODEL 203.0 /2 /7 as of 24.4.04 except CODE (581) Comfort automatic air conditioning

Identifying Convenience Automatic Air Conditioning Box Design. Scheme 16

Scheme 41: Locating Automatic Air Conditioning Box
Automatic air conditioning box, locationThe automatic air conditioning box (1) is below the instrument panel.
Automatic air conditioning box, purposeGF83.40-P-2105-03P
Automatic air conditioning box, designGF83.40-P-2105-04P
Automatic air conditioning box functionGF83.40-P-2105-02P

Evaporator location/task/design/function - GF83.40-P-2121P

MODEL 203.0 /2 /7 with CODE (580) Air conditioning (or Tempmatic for USA) with CODE (580) Automatic air conditioning with CODE (581) Automatic air conditioning with CODE (581) Comfort automatic air conditioning

MODEL 209.3/ 4

Identifying Evaporator. Scheme 17

Scheme 17: Identifying Evaporator
Evaporator, locationThe evaporator (1) is in the air conditioning housing beneath the instrument panel.
Evaporator, purposeThe evaporator (1) is used to cool and dehumidify the interior air.
Evaporator, designThe evaporator (1) essentially comprises soldered semicircular disks with corrugated louver fins.
Evaporator, functionGF83.40-P-2121-01P

Expansion valve, location/task/design/function - GF83.40-P-2123P

MODEL 203.0 /2 /7 with CODE (580) Air conditioning (or Tempmatic for USA) with CODE (580) Automatic air conditioning with CODE (581) Automatic air conditioning with CODE (581) Comfort automatic air conditioning

MODEL 209.3 /4

MODEL 211.0 /2 /6

Shown on model 203

Locating Expansion Valve. Scheme 18

Scheme 18: Locating Expansion Valve
Expansion valve, positionThe expansion valve (5) is located in the left rear of the engine compartment.
Expansion valve, taskThe expansion valve (5) sprays liquid refrigerant into the evaporator. There the ambient air is cooled down to approx. 1.5 °C and conveyed to the AC housing. The quantity injected is dependent here on the pressure and temperature of the flowing refrigerant.
Expansion valve, designGF83.40-P-2123-03P
Expansion valve, functionGF83.40-P-2123-01P

Electric fan motor/air conditioning system, location/task/function - GF83.40-P-2151P

MODEL 203.0 /2 /7 with CODE (580) Air conditioning (or Tempmatic for USA) with CODE (580) Automatic air conditioning with CODE (581) Automatic air conditioning with CODE (581) Comfort automatic air conditioning

Locating Engine And AC Electric Suction Fan With Integrated Control. Scheme 19

Scheme 19: Locating Engine And AC Electric Suction Fan With Integrated Control
Electric fan, engine/air conditioningThe electric suction fan engine and AC with integrated control (M4/7) is located behind the radiator.
Electric fan, engine/air conditioning, taskThe engine and AC electric suction fan with integrated control (M4/7) is used to cool down the coolant and the refrigerant.
Engine/air conditioning electric fanGF83.40-P-2118-01P

Condenser location/task/function - GF83.40-P-2152P

MODEL 203.0 /2 /7 with CODE (580) Air conditioning (or Tempmatic for USA) with CODE (580) Automatic air conditioning with CODE (581) Automatic air conditioning with CODE (581) Comfort automatic air conditioning

Identifying Automatic Air Conditioning Control And Operating Unit - Shown On AAC [KLA] Control And Operating Unit (N22) As From 1.6.02. Scheme 20

Scheme 49: Locating Condenser
Condenser positionThe condenser (3) is located behind the radiator grille directly in front of the radiator.
Condenser taskThe condenser (3) ensures that the refrigerant coming from the evaporator changes state from gas to liquid.
Condenser functionGF83.40-P-2120-01P

Air conditioning coolant temperature sensor location/task/function - GF83.40-P-2155P

MODEL 203.0 /2 /7 with CODE (580) Air conditioning (or Tempmatic for USA) with CODE (580) Automatic air conditioning with CODE (581) Automatic air conditioning with CODE (581) Comfort automatic air conditioning

Identifying Coolant Temperature Sensor. Scheme 21

Scheme 21: Identifying Coolant Temperature Sensor
Air conditioning coolant temperature sensor, positionThe coolant temperature sensor (B11/4) is located at the front of the engine.
Air conditioning coolant temperature sensor, taskThe coolant temperature sensor (B11/4) records the temperature of the coolant.
Air conditioning coolant temperature sensor, functionGF83.40-P-2125-01P
Scheme 16: Identifying Convenience Automatic Air Conditioning Box Design

Convenience air conditioner housing, location/task/design/function - GF83.40-P-2170P

MODEL 203.0 /2 /7 up to 31.5.01 with CODE (581) Air conditioning (Automatic)

MODEL 203.0 /2 /7 as of 1.6.01 with CODE (581) Convenience automatic air conditioning

Locating Comfort Automatic Air Conditioning Housing. Scheme 22

Scheme 22: Locating Comfort Automatic Air Conditioning Housing
Comfort automatic air conditioning housing, locationThe comfort automatic air conditioning housing (1) is located below the instrument panel.
Convenience automatic air conditioning box designGF83.40-P-2170-01P
Comfort automatic air conditioning housing, taskGF83.40-P-2170-02P
Convenience automatic air conditioning box, functionGF83.40-P-2170-03P

Refrigerant pressure and temperature sensor location/task/function - GF83.40-P-2171P

MODEL 203.0 /2 /7 with CODE (580) Air conditioning (or Tempmatic for USA) with CODE (580) Automatic air conditioning with CODE (581) Automatic air conditioning with CODE (581) Comfort automatic air conditioning

Locating Refrigerant Pressure And Temperature Sensor. Scheme 23

Scheme 23: Locating Refrigerant Pressure And Temperature Sensor
Refrigerant pressure and temperature sensor, positionThe refrigerant pressure and temperature sensor (B12/2) is located at the bottom of the condenser (3) in the engine compartment.
Refrigerant pressure and temperature sensor, taskThe refrigerant pressure and temperature sensor (B12/2) records the refrigerant pressure and refrigerant temperature and passes on these values to the AAC [KLA] control and operating unit or to the comfort AAC [KLA] control and operating unit.
Refrigerant pressure and temperature sensor, functionGF83.40-P-2171-01P

Control and operating unit for automatic air conditioning, location/task - GF83.40-P-2180PP

MODEL 203.0 /2 /7 up to 31.5.01 with CODE (580) Air conditioning (or Tempmatic for USA)

MODEL 203.0 /2 /7 as of 1.6.01 up to 23.4.04 with CODE (580) Automatic air conditioning

Identifying AAC (KLA) Control And Operating Unit - Model 203.0 /2 /7 Up To 31.5.01 And As Of 1.6.01 Up To 23.4.04 With Code (580). Scheme 24

Scheme 24: Identifying AAC (KLA) Control And Operating Unit - Model 203.0 /2 /7 Up To 31.5.01 And As Of 1.6.01 Up To 23.4.04 With Code (580)
Automatic air conditioning control and operating unit, locationThe AAC control and operating module (N22) is located in the center console.
Automatic air conditioning control and operating unit, taskGF83.40-P-2180-01PP

Control and operating unit for automatic air conditioning, location/task - GF83.40-P-2180PQ

MODELS 203.0 /2 /7 as of 24.4.04 except CODE (581) Comfort automatic air conditioning

Identifying Refrigerant Compressor Control Valve And Compressor - Shown On Model 203. Scheme 25

Scheme 63: Identifying AAC (KLA) Control And Operating Unit - Models 203.0 /2 /7 As Of 24.4.04 Except Code (581)
Automatic air conditioning control and operating unit, locationThe AAC control and operating unit (N22) is located in the center console.
Automatic air conditioning control and operating unit, taskGF83.40-P-2180-01PQ

Control and operating unit comfort automatic air conditioning location/task - GF83.40-P-2181PP

MODELS 203.0 /2 /7 up to 31.5.01 with CODE (581) Automatic air conditioning

MODELS 203.0 /2 /7 as of 1.6.01 up to 23.4.04 with CODE (581) Comfort automatic air conditioning

Identifying Comfort Acc (KLA) Control And Operating Unit - Models 203.0 /2 /7 Up To 31.5.01 And As Of 1.6.01 Up To 23.4.04 With Code (581). Scheme 26

Scheme 26: Identifying Comfort Acc (KLA) Control And Operating Unit - Models 203.0 /2 /7 Up To 31.5.01 And As Of 1.6.01 Up To 23.4.04 With Code (581)
Control and operating unit comfort automatic air conditioning, locationThe comfort AAC control and operating unit (N22/7) is located in the center console.
Control and operating unit comfort automatic air conditioning, taskGF83.40-P-2181-01PP

Control and operating unit comfort automatic air conditioning location/task - GF83.40-P-2181PQ

MODEL 203.0 /2 /7 as of 24.4.04 with CODE (581) Comfort automatic air conditioning

Identifying Comfort AAC Control And Operating Unit - Model 203.0 /2 /7 As Of 24.4.04 With Code (581). Scheme 27

Scheme 27: Identifying Comfort AAC Control And Operating Unit - Model 203.0 /2 /7 As Of 24.4.04 With Code (581)
Control and operating unit comfort automatic air conditioning, locationThe comfort AAC control and operating unit (N22/7) is located in the center console
Control and operating unit comfort automatic air conditioning, taskGF83.40-P-2181-01PQ

Actuator motors for automatic air conditioning, location/task/function - GF83.40-P-2182P

MODEL 203.0 /2 /7 up to 31.5.01 with CODE (580) Air conditioning (or Tempmatic for USA)

MODEL 203.0 /2 /7 as of 1.6.01 with CODE (580) Automatic air conditioning

MODEL 203.0 /2 /7 as of 24.4.04 except CODE (581) Comfort automatic air conditioning

Identifying Actuator Motors For Automatic Air Conditioning - Model 203.0 /2 /7 Up To 31.5.01 And As Of 1.6.01 With Code (580) And As Of 24.4.04 Except Code (581). Scheme 28

Scheme 28: Identifying Actuator Motors For Automatic Air Conditioning - Model 203.0 /2 /7 Up To 31.5.01 And As Of 1.6.01 With Code (580) And As Of 24.4.04 Except Code (581)
Automatic air conditioning actuator motors, locationThe actuator motors (M2/5, M2/6, M2/7, M2/15, M2/16, M2/21) are on the A/C housing.
Automatic air conditioning actuator motors, taskGF83.40-P-2182-01P
Automatic air conditioning actuator motors, functionGF83.40-P-2182-02P

Actuator motors for comfort automatic air conditioning, location/task/function - GF83.40-P-2183P

MODEL 203.0 /2 /7 up to 31.5.01 with CODE (581) Automatic air conditioning

MODEL 203.0 /2 /7 as of 1.6.01 with CODE (581) Comfort automatic air conditioning

Identifying Actuator Motors For Comfort Automatic Air Conditioning. Scheme 29

Scheme 29: Identifying Actuator Motors For Comfort Automatic Air Conditioning
Comfort automatic air conditioning actuator motors, locationThe actuator motors (A32m2), (M2/5), (M2/6), (M2/7), (M2/8), (M2/9), (M2/10), (M2/11), (M2/19), M2/20) are on the A/C housing.
Comfort automatic air conditioning actuator motors, taskGF83.40-P-2183-01P
Comfort automatic air conditioning actuator motors, functionGF83.40-P-2183-02P

Automatic air conditioning system component summary, location/ task/design/function - GF83.40-P-9990P

MODEL 203.0 /2 /7 up to 31.5.01 with CODE (580) Air conditioning (or Tempmatic for USA)

MODEL 203.0 /2 /7 as of 1.6.01 with CODE (580) Automatic air conditioning

MODEL 203.0 /2 /7 as of 24.4.04 except CODE (581) Comfort automatic air conditioning

Control and operating unit for automatic air conditioning, location/taskOn vehicles up to 23.4.04GF83.40-P-2180PP
On vehicles as from 24.4.04 without code (581) Comfort automatic air conditioningGF83.40-P-2180PQ
Front SAM control unit with fuse and relay module, location/task/designGF54.21-P-4108PP
Front driver side door control unit, location/task/ design/functionGF72.29-P-4105PP
Front passenger door control unit, location/task/ design/functionGF72.29-P-4106PP
Rear door control unit, location / task / design /functionFor model 203.0/2GF72.29-P-4102PP
Electronic ignition switch control unit, location/ task/design/functionGF80.57-P-4102PP
Overhead control panel control unit, location/ task/designGF82.20-P-4110A
Air ducting, location/task/functionGF83.10-P-2182P
Actuator motors for automatic air conditioning, location/task/functionGF83.40-P-2182P
Blower motor, location/task/functionGF83.10-P-2140P
Blower regulator, location/task/functionGF83.10-P-2141P
Heating system heat exchanger, location/task/ functionGF83.20-P-2108P
Heater water circulation pump, location/task/functionIn vehicles with code (450) Taxi version or code (670) Residual engine heat utilization system (REST [MRA])GF83.20-P-2109P
Dust filter, location/task/functionGF83.10-P-2142P
Air conditioner housing, location/task/design/ functionGF83.40-P-2105P
Electric fan motor/air conditioning system, location/task/functionGF83.40-P-2151P
Condenser location/task/functionGF83.40-P-2152P
Evaporator location/task/design/functionGF83.40-P-2121P
Fluid reservoir location/task/design/functionGF83.40-P-2122P
Expansion valve, location/task/design/functionGF83.40-P-2123P
Air conditioning coolant temperature sensor location/task/functionGF83.40-P-2155P
Refrigerant pressure and temperature sensor location/task/functionGF83.40-P-2171P
Refrigerant compressor, location/task/design/ functionGF83.55-P-2100P
Refrigerant compressor control valve location/ task/functionGF83.55-P-2102P
Belt pulley, location/task/design/functionGF83.55-P-2103P
Pressure relief valve location/task/functionGF83.55-P-2104P
Evaporator core temperature sensor, location/ task/functionGF83.57-P-2109P
Outside temperature sensor, location/task/ functionOn vehicles up to 23.4.04GF83.57-P-2110P
In vehicles as of 24.4.04GF83.57-P-2110PP
Air humidity sensor, location/task/design/functionIn vehicles up to 28.6.06GF83.30-P-2125P
Table of contents, automatic air conditioning (AAC) function descriptionGF83.40-P-0999P

Refrigerant compressor, location/task/design/function - GF83.55-P-2100P

ENGINE 111, 112, 113, 271, 272, 611, 612, 642, 646 in MODEL 203.0 /2 with CODE (580) Air conditioning (or Tempmatic for USA) with CODE (580) Automatic air conditioning with CODE (581) Automatic air conditioning with CODE (581) Comfort automatic air conditioning

ENGINE 111, 112, 271, 272, 611, 612, 646 in MODEL 203.7 with CODE (580) Air conditioning (or Tempmatic for USA) with CODE (580) Automatic air conditioning with CODE (581) Automatic air conditioning with CODE (581) Comfort automatic air conditioning

ENGINE 112.942 /970, 113.942 /965 /981, 612.963, 628.963 in MODEL 163 as of 1.9.01 with CODE (580) Automatic air conditioning

ENGINE 112, 113, 271, 272, 273, 612, 642, 646 in MODEL 209.3

ENGINE 112, 113, 271, 272, 273, 642 in MODEL 209.4

Shown on model 203

Locating Ambient Temperature Display Temperature Sensor - Model 203. Scheme 30

Scheme 72: Identifying Refrigerant Compressor - Shown On Model 203
Refrigerant compressor, positionThe refrigerant compressor (A9) is flange-mounted to the left front of the engine.
Model 163GF83.55-P-2100-01GH
Refrigerant compressor, taskThe refrigerant compressor (A9) is responsible for induction and compression of the refrigerant.
Refrigerant compressor, designGF83.55-P-2100-03P
Refrigerant compressor, functionGF83.55-P-2100-02P

Identifying Refrigerant Compressor Control Valve, Function - Variable Volume Control In Partial Load Range. Scheme 31

Scheme 31: Identifying Refrigerant Compressor Control Valve, Function - Variable Volume Control In Partial Load Range

Variable volume control in partial load range

(e.g. at low ambient temperature or low cooling capacity requirement)

Essentially, the cooling output is dependent on the intake pressure, i.e. if the suction pressure (Ps) drops below the diaphragm pressure (Ps1) in the refrigerant compressor control valve and the regulating current is reduced at the same time, then the passage from high pressure (Pd) to crankcase pressure (Pc) is released by the control plunger (2) in the refrigerant compressor control valve. As a result, refrigerant flows from the high pressure side into the crankcase which results in an increase in crankcase pressure (Pc).

The sum of the forces on the left-hand side, resulting from the crankcase pressure (Pc), the return force (centrifugal force) of the swash plate and the spring return force thus becomes greater than total piston forces. The swash plate moves into a vertical position, which causes a reduction in piston travel and replacement volume.

In addition, a regulation of the cooling output takes place as a function of the air humidity, i.e. at high air humidity there is an external actuation of the control valve, achieving a post-regulation of the cooling output (preventing fogging up of the windows).

The refrigerant compressor is automatically switched off at a volumetric flow of less than 5 cm 3 .

Identifying Refrigerant Compressor Control Valve, Function - Control At Max. Swept Volume. Scheme 32

Scheme 32: Identifying Refrigerant Compressor Control Valve, Function - Control At Max. Swept Volume

Control at max. swept volume

(e.g. at higher ambient temperature or higher cooling capacity requirement)

If the suction pressure (Ps) rises above the diaphragm pressure (Ps1) in the refrigerant compressor control valve and the control current is increased at the same time, in the refrigerant compressor control valve the passage - high pressure (Pd) to crankcase pressure (Pc) - is closed by the control plunger (2). The crankcase pressure (Pc) drops, as no refrigerant flows from the high pressure side into the crankcase via the refrigerant compressor control valve.

In the long-term the bypass (1) sets up a pressure compensation between the suction pressure (Ps) and crankcase pressure (Pc), i.e. the sum of the reaction forces on the left side, resulting from the crankcase pressure (Pc), return force of the swash plate (centrifugal force) and the spring return force, is therefore smaller than the sum of the piston forces. The swash plate angle extends to beyond the "0-position ", i.e. the inclined position increases continuously to the swash plate's mechanical limit stop at the stop plate. The piston stroke increases linear to the swash plate's inclination till it reaches max. volumetric flow.

Control valve, location/task/function - GF83.55-P-2102P

ENGINE 111, 112, 113, 271, 272, 611, 612, 642, 646 in MODEL 203.0 /2 with CODE (580) Air conditioning (or Tempmatic for USA) with CODE (580) Automatic air conditioning with CODE (581) Automatic air conditioning with CODE (581) Comfort automatic air conditioning

ENGINE 111, 112, 271, 272, 611, 612, 646 in MODEL 203.7 with CODE (580) Air conditioning (or Tempmatic for USA) with CODE (580) Automatic air conditioning with CODE (581) Automatic air conditioning with CODE (581) Comfort automatic air conditioning

ENGINE 112.942 /970, 113.942 /965 /981, 612.963, 628.963 in MODEL 163 as of 1.9.01 with CODE (580) Automatic air conditioning

ENGINE 112, 113, 271, 272, 273, 612, 642, 646 in MODEL 209.3

ENGINE 112, 113, 271, 272, 273, 642 in MODEL 209.4

Shown on model 203

Scheme 25: Identifying Refrigerant Compressor Control Valve And Compressor - Shown On Model 203
Refrigerant compressor control valve, positionThe refrigerant compressor control valve (1) is located on the refrigerant compressor (A9).
Refrigerant compressor control valve, taskThe refrigerant compressor control valve (1) regulates the swept volume of the refrigerant compressor (A9) dependent upon the refrigerant capacity requirement.
Refrigerant compressor control valve, functionGF83.55-P-2102-02P

Belt pulley, location/task/design/function - GF83.55-P-2103P

ENGINE 111, 112, 113, 271, 272, 611, 612, 642, 646 in MODEL 203.0 /2 with CODE (580) Air conditioning (or Tempmatic for USA) with CODE (580) Automatic air conditioning with CODE (581) Automatic air conditioning with CODE (581) Comfort automatic air conditioning

ENGINE 111, 112, 271, 272, 611, 612, 646 in MODEL 203.7 with CODE (580) Air conditioning (or Tempmatic for USA) with CODE (580) Automatic air conditioning with CODE (581) Automatic air conditioning with CODE (581) Comfort automatic air conditioning

ENGINE 112.942 /970, 113.942 /965 /981, 612.963, 628.963 in MODEL 163 as of 1.9.01 with CODE (580) Automatic air conditioning

ENGINE 112, 113, 271, 272, 273, 612, 642, 646 in MODEL 209.3

ENGINE 112, 113, 271, 272, 273, 642 in MODEL 209.4

Shown on model 203

Locating Belt Pulley And Refrigerant Compressor - Shown On Model 203. Scheme 33

Scheme 33: Locating Belt Pulley And Refrigerant Compressor - Shown On Model 203
Belt pulley, positionThe belt pulley (2) is located on the front of the drive shaft on the refrigerant compressor (A9).
Belt pulley, taskThe belt pulley (2) drives the refrigerant compressor (A9). In addition the pulley (2) is also used as a torque damper and a torque limiter.
Belt pulley, designGF83.55-P-2103-03P
Belt pulley, functionGF83.55-P-2103-02P

Pressure relief valve, location / task / function - GF83.55-P-2104P

ENGINE 111, 112, 113, 271, 272, 611, 612, 642, 646 in MODEL 203.0 /2 with CODE (580) Air conditioning (or Tempmatic for USA) with CODE (580) Automatic air conditioning with CODE (581) Automatic air conditioning with CODE (581) Comfort automatic air conditioning

ENGINE 111, 112, 271, 272, 611, 612, 646 in MODEL 203.7 with CODE (580) Air conditioning (or Tempmatic for USA) with CODE (580) Automatic air conditioning with CODE (581) Automatic air conditioning with CODE (581) Comfort automatic air conditioning

ENGINE 112.942 /970, 113.942 /965 /981, 612.963, 628.963 in MODEL 163 as of 1.9.01 with CODE (580) Automatic air conditioning

ENGINE 112, 113, 271, 272, 273, 612, 642, 646 in MODEL 209.3

ENGINE 112, 113, 271, 272, 273, 642 in MODEL 209.4

Shown on model 203

Identifying Pressure Relief Valve And Refrigerant Compressor - Shown On Model 203. Scheme 34

Scheme 34: Identifying Pressure Relief Valve And Refrigerant Compressor - Shown On Model 203
Pressure relief valve, positionThe pressure relief valve (3) is located on the refrigerant compressor (A9).
Pressure relief valve, taskThe pressure relief valve (3) serves to protect the refrigerant circuit from damage caused by excess pressure.
Pressure relief valve, functionGF83.55-P-2104-02P

Outside temperature sensor, location/task/design/function - GF83.57-P-2103R

MODEL 230

Locating Ambient Temperature Display Temperature Sensor - Model 230. Scheme 35

Scheme 35: Locating Ambient Temperature Display Temperature Sensor - Model 230
Outside air temperature sensor positionThe outside temperature indicator temperature sensor (B14) is in the bumper, at the left-hand side.
Outside air temperature sensor purposeRecording outside temperature as electrical value for displaying the outside temperature on the instrument cluster (A1) and controlling various functions that are dependent on the outside air temperature.
Outside air temperature sensor designThe sensor is in a housing made from top quality plastic that is firmly clipped to the vehicle.
Outside air temperature sensor functionThe outside temperature indicator temperature sensor (B14) is a temperature dependent resistance with negative temperature coefficients (NTC). The outside temperature indicator temperature sensor (B14) changes its resistance with increasing temperature .

Outside temperature sensor, location/task/design/function - GF83.57-P-2103S

MODELS 215, 220

Shown on MODEL 220

Locating Ambient Temperature Display Temperature Sensor - Model 220. Scheme 36

Scheme 36: Locating Ambient Temperature Display Temperature Sensor - Model 220
Outside air temperature sensor positionThe ambient temperature display temperature sensor (B14) is located at the left side of the front bumper
Outside air temperature sensor taskThe ambient temperature display temperature sensor (B14) records the ambient temperature.
Outside air temperature sensor designThe outside temperature display temperature sensor (B14) is a temperature-dependent resistance with negative temperature coefficient (NTC).
Outside air temperature sensor functionThe outside temperature display temperature sensor (B14) records the outside air temperature, converts it into an electrical signal and transmits it to the left front SAM control unit.

Evaporator core temperature sensor, location/task/function - GF83.57-P-2109P

MODEL 203.0 /2 /7 with CODE (580) Air conditioning (or Tempmatic for USA) with CODE (580) Automatic air conditioning with CODE (581) Automatic air conditioning with CODE (581) Comfort automatic air conditioning

MODEL 209.3/ 4

Shown on model 203

Locating Evaporator Temperature Sensor - Model 203. Scheme 37

Scheme 37: Locating Evaporator Temperature Sensor - Model 203
Temperature sensor evaporator core, positionThe evaporator temperature sensor (B10/6) is located in the air flow downstream of the left evaporator in the air conditioner housing.
Evaporator temperature sensor, taskThe evaporator temperature sensor (B10/6) records the evaporator temperature.
Evaporator temperature sensor, functionGF83.57-P-2102-02P

Outside temperature sensor, location/task/function - GF83.57-P-2110P

MODELS 203.0 /2 /7 up to 23.4.04

Illustrated on Model 203.0

Scheme 30: Locating Ambient Temperature Display Temperature Sensor - Model 203
Outside air temperature sensor positionThe ambient temperature display temperature sensor (B14) is located at the left side of the front bumper
Outside air temperature sensor taskTo record the outside temperature.
Outside air temperature sensor functionGF83.57-P-2103-01P

Outside temperature sensor, location/task/function - GF83.57-P-2110PP

MODELS 203.0 /2 /7 as of 24.4.04

Illustrated on Model 203.0

Locating Ambient Temperature Display Temperature Sensor - Illustrated On Model 203.0. Scheme 38

Scheme 38: Locating Ambient Temperature Display Temperature Sensor - Illustrated On Model 203.0
Outside air temperature sensor positionThe ambient temperature display temperature sensor (B14) is located at the right side in the front bumper
Outside air temperature sensor taskTo record the outside temperature.
Outside air temperature sensor functionThe outside temperature display temperature sensor (B14) changes its resistance depending on the outside temperature. It is discretely read in by the front SAM control unit with fuse and relay module.

Sun sensor, location/task/function - GF83.57-P-2111P

MODEL 203 up to 31.5.01 with CODE (581a) Air conditioning (Automatic)

MODEL 203 as of 1.6.01 with CODE (581b) comfort automatic air conditioning

MODELS 209.3 /4 with CODE (581b) comfort automatic air conditioning

Shown on model 203

Locating C-AAC Sun Sensor - Shown On Model 203. Scheme 39

Scheme 39: Locating C-AAC Sun Sensor - Shown On Model 203
Sun sensor, positionThe C-AAC sun sensor (4 in total) (B32/2) is located at the engine hood center air inlet.
Sun sensor, taskThe C-AAC sun sensor (4 in total) (B32/2) records the intensity and insulation direction.
Sun sensor, functionGF83.57-P-2104-01P

Stationary heater/heater booster control unit, location/task - GF83.70-P-4002A

MODEL 168 with ENGINE 668.940 with heater booster

MODEL 202 with ENGINE 611.960 with heater booster

MODEL 210 with heater booster

MODEL 220 with ENGINE 613.960 with heater booster

MODEL 220 with ENGINE 628.960 with heater booster

MODEL 129 as of 1.6.97 with CODE (228) Stationary heater

MODEL 203 up to 23.4.04, models 210, 215, 220, 230 with CODE (228) Stationary heater

MODEL 463 as of 1.6.94 with CODE (H12) Auxiliary heater Webasto Tele Thermo Top S

MODEL 209.3 up to 31.5.04 with CODE (228) Stationary heater

Models 129, 168, 202, 203, 209.3, 215, 220, 230

Identifying Stationary Heater/Heater Booster Control Unit - Model 203 Up To 23.4.04, Models 210, 215, 220, 230 With Code (228) Stationary Heater. Scheme 40

Scheme 40: Identifying Stationary Heater/Heater Booster Control Unit - Model 203 Up To 23.4.04, Models 210, 215, 220, 230 With Code (228) Stationary Heater
Stationary heater/heater booster control unit positionThe STH control unit (A6n1) or STH or HB control unit (A6n1) is located at the STH heater unit in models 129, 203, 230, 209.3 or the STH or HB heater unit in models 168, 202, 220. It forms an inseparable unit together with the heat exchanger (1).
Model 210 up to 31.08.96 with engine 602.982 with heater boosterGF83.70-P-4002-01A
Model 210 with code (228) Stationary heater Model 463 as of 01.06.94 with code (H12) Webasto Tele Thermo Top S auxiliary heater
Stationary heater/heater booster control unit, taskGF83.70-P-4002-02A

Stationary heater/heater booster control unit, location/task - GF83.70-P-4002P

MODELS 203.0 /2 /7 as of 24.4.04 with CODE (228) Stationary heater

Locating STH Heater Unit And STH Control Unit - Models 203.0 /2 /7 As Of 24.4.04 With Code (228) Stationary Heater. Scheme 41

Scheme 41: Locating STH Heater Unit And STH Control Unit - Models 203.0 /2 /7 As Of 24.4.04 With Code (228) Stationary Heater
Stationary heater/heater booster control unit positionThe STH control unit (A6n1) is a constituent of the STH heater unit (A6), which is located in the front area of the right wheelhouse.
Stationary heater/heater booster control unit, taskGF83.70-P-4002-02P