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Air Distribution in A/C and Air Intake Units, Block Diagram






Air Distribution in A/C and Air Intake Units, Block Diagram

Air routing and air distribution in passenger compartment => [ Air Routing and Distribution in Passenger Compartment ]

Air routing in the air intake unit and in the A/C unit => [ Air Routing in Air Intake and A/C Units ].

Installation location of individual components outside the passenger compartment => [ A/C Control and Regulation Components outside Passenger Compartment ] A/C Control and Regulation Components outside Passenger Compartment.

Installation locations of the individual components in the passenger compartment => [ A/C System Control and Regulation Components inside Passenger Compartment ] Description and Operation.

=> [ A/C Unit Air Inlet and Vents ]

=> [ Air Routing in Air Intake and A/C Units ]

=> [ Air Routing and Distribution in Passenger Compartment ]

A/C Unit Air Inlet and Vents





1 Air Conditioner Unit

Different versions depending on the version and vehicle equipment (Climatronic Control Module (J255) A./C control head, "Basic" or "Comfort" version, left or right-hand steering, vehicles with or without the Auxiliary Air Heater Heating Element (Z35)).

Heating & A/C unit components => [ A/C Components ] A/C Components

Air routing in the passenger compartment => [ Air Routing and Distribution in Passenger Compartment ]

Heating and A/C unit, removing and installing => [ A/C Unit ] A/C Unit

2 To Center Instrument Panel Vent

3 To Rear Center Console Vent

4 To Right Instrument Panel Vent

Via an air duct installed in the instrument panel to the right instrument panel vent (chest vent)

5 To Indirect Ventilation Vent

Via the air ducts in the instrument panel to the vents in the upper instrument panel cover.

Air comes out of this vent only in vehicles with the "Comfort" version of the Climatronic Control Module (J255) A/C control head. In vehicles equipped with the "Basic" version of the Climatronic Control Module (J255) A/C control head, the opening in the A/C unit is sealed (different A/C versions).

The door in the A/C unit is opened e.g. when setting the "air for the instrument panel chest vents" on the "Comfort" version of the Climatronic (J255) control module A/C control head.

6 To Instrument Panel Defroster Vent

Via an air duct installed in the instrument panel to the windshield and to the vents in the left and right front doors.

7 To Left Instrument Panel Vent

Via an air duct installed in the instrument panel to the left instrument panel vent (chest vent)

8 To Right Footwell Vents

9 To Left Footwell Vents

10 Air Inlet From Air Intake Unit

Air Routing in Air Intake and A/C Units





1 Plenum Chamber

2 Passenger Compartment

3 Air Intake Unit

4 Air Conditioner Unit

5 Cut Line Through Air Intake Unit

The cross sectional display shows the air intake unit as if it were cut in half along this line.

6 Fresh-Air Intake From Plenum Chamber

In fresh air mode, air is drawn in beneath plenum chamber cover

7 Recirculating Air Intake Behind Instrument Panel

In recirculated air mode, air is drawn in via an opening in the plenum chamber wall beneath the instrument panel.

8 Air Outlet From Air Intake Unit Into A/C Unit

A grommet for routing the air is installed between the A/C unit and the opening in the plenum chamber wall.

9 Cut Line Through A/C Unit

The cross sectional display shows the A/C unit as if it were cut in half along this line.

10 Fresh Air Blower (V2)

Removing and installing => [ Fresh Air Blower ] Service and Repair

11 Dust and Pollen Filter

Follow the replacement intervals.

Different versions depending on vehicle equipment and production time frame.

Removing and installing => [ Dust and Pollen Filter ] Dust and Pollen Filter

12 Evaporator

13 Cold Air Channel

This channel guides the air past the heat exchanger to the center instrument panel vent

14 Heater Unit Heat Exchanger

Removing and installing => [ A/C Unit Heat Exchanger ] A/C Unit Heat Exchanger

15 Auxiliary Heater Heating Element (Z35)

Not for North American market.

16 To Rear Center Console Vent

And to the vents in the "B pillars" (only installed in vehicles with the "Comfort" version of the Climatronic Control Module (J255) A/C control head).

17 Cold Air Door

This door is actuated by the Control Motor for the Front Cold Air Door (V197)

18 To the center instrument panel vent

19 Center Vent Door

This door is actuated by the Control Motor for the Center Vent (V102).

20 To Left Footwell Vents

21 To Right Instrument Panel Vent

Via an air duct installed in the instrument panel to the right instrument panel vent

22 To Instrument Panel Defroster Vent

Via an air duct installed in the instrument panel to the windshield and to the vents in the left and right front doors

Air Routing and Distribution in Passenger Compartment

Air intake and air guide in air conditioner => [ A/C Unit Air Inlet and Vents ]

Installation locations of the individual components in the passenger compartment => [ A/C System Control and Regulation Components inside Passenger Compartment ] Description and Operation.





1 Air Conditioner Unit

Different versions (Climatronic Control Module (J255) A./C control head, "Basic" and "Comfort" versions, vehicle with left or right-hand steering, vehicle with or without the Auxiliary Air Heater Heating Element (Z35)).

Heating & A/C unit components => [ A/C Components ] A/C Components

Air routing in the air intake unit and in the A/C unit => [ Air Routing in Air Intake and A/C Units ].

Heating and A/C unit, removing and installing => [ A/C Unit ] A/C Unit

2 Instrument Panel Air Duct

To the front windshield "Defrost" vent, to the vents in the front doors

For vehicles with the "Comfort" version of the Climatronic Control Module (J255) A/C control head, in addition to the vents for indirect ventilation

The air duct is part of the instrument panel and cannot be replaced individually

Removing and installing the instrument panel cover and vent

3 To Left Front Door Vent Intermediate Piece

Removing and installing

4 Front Windshield Defrost Vents

Removing and installing the instrument panel cover and vent

5 Indirect Ventilation Vents

Air comes out of this vent only in vehicles with the "Comfort" version of the Climatronic Control Module (J255) A/C control head. In vehicles equipped with the "Basic" version of the Climatronic Control Module (J255) A/C control head, the opening in the A/C unit is sealed (different A/C versions).

Via the air ducts in the instrument panel to the vents in the upper instrument panel cover.

6 To Right Front Door Vent Intermediate Piece

Removing and installing

7 Intermediate Piece To Left Front Door Vent

Removing and installing

8 Intermediate Piece To Right Front Door Vent

Removing and installing

9 Left Instrument Panel Vent

Removing and installing

10 Air Duct To Left And Right Instrument Panel Vents

Remove and install the instrument panel air duct

11 Right Instrument Panel Vent

Removing and installing

12 Center Instrument Panel Vent

Removing and installing

13 Intermediate Piece To Instrument Panel Air Ducts

Removing and installing

14 Left Front Footwell Vent

The footwell vent is part of the driver's side storage compartment

15 Right Front Footwell Vent

The footwell vent is part of the glove compartment or related cover

16 Intermediate Piece To Left Footwell Vents

17 Intermediate Piece To Right Footwell Vents

18 Left Rear Footwell Vent

The air flows out under the seat

19 Air Duct To Rear Center Console Vent

For vehicles with the "Comfort" version of the Climatronic Control Module (J255) A/C control head, in addition to the vents in the "B pillars".

For vehicles with the "Basic" version of the Climatronic Control Module (J255) A/C control head, the connections for the air ducts to the vents in the "B pillars" are sealed closed.

20 Left Rear Footwell Vent

The air flows out under the seat

21 Vent In Center Console

Removing and installing

22 Air Duct To Left B Pillar Vent

Only installed in vehicles with the "Comfort" version of the Climatronic Control Module (J255) A/C control head.

23 Left B Pillar Vent

Only installed in vehicles with the "Comfort" version of the Climatronic Control Module (J255) A/C control head.

Removing and installing

24 Left B Pillar Vent

Only installed in vehicles with the "Comfort" version of the Climatronic Control Module (J255) A/C control head.

Removing and installing