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Heater and ventilation system,
servicing
Special tools
These are the special tools required for the procedures in
this repair group.
Before starting repairs, review the following points:
Make certain that you have all of the necessary tools and
parts on hand to complete the job
Read all of the instructions thoroughly and do not attempt
shortcuts
When parts are required, only use, replacement parts
that meet Audi specifications
Use the appropriate tool for each task. Makeshift tools,
parts and procedures will not make good repairs
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Instrument panel air ducts, removing and
installing
Note:
Interior air exits the passenger compartment through the
rear hat shelf, and through two extraction vents in the
trunk.
Removing and installing extraction vents Fig. 13 .
1 - Instrument panel
Removing and installing Repair Manual, Body
Exterior, Interior,Repair Group 70
2 - Screw
3 - Screw
4 - Defroster duct (connector piece)
5 - Seal carrier
6 - Seal carrier
7 - Air duct
8 - Retainer
9 - Bolts
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10 - Defroster vent (right door window)
Removing and installing Fig. 6
11 - Instrument panel air outlet (passenger side)
Removing and installing Fig. 7
Removing and installing swivel vents Fig. 12
12 - Defroster vent (windshield)
Removing and installing Fig. 8
13 - Defroster vent (left door window)
Removing and installing Fig. 6
14 - Instrument panel air outlet (center)
Removing and installing Fig. 9
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15 - Rear air outlet (center)
Removing and installing Fig. 10
16 - Instrument panel air outlet (driver's side, lower)
Removing and installing Fig. 11
Not installed on all cars
17 - Instrument panel air outlet (driver's side, upper)
Removing and installing Fig. 11
Removing and installing swivel vents Fig. 12
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Fig. 6 Removing and installing defroster vent (right and left door window)
- Lift up front of vent.
- Slide vent sideways and out (arrow).
- Install in reverse order of removal.
Ensure that retaining lug engages slide -A-.
Fig. 7 Removing and installing instrument panel air outlet (passenger
side)
- Insert wire hooks -A -through center of vent, one hook on each side.
Making wire hooks -A- Fig. 14
- Using wire hooks, pull vent from instrument panel.
Note:
If removing and installing swivel vents Fig. 12 .
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Fig. 8 Removing and installing defroster vent (windshield)
- Remove instrument panel Repair Manual, Body Exterior, Interior,Repair
Group 70.
- Remove 3 nuts and remove vent.
Fig. 9 Removing and installing instrument panel air outlet (center)
- Insert wire hooks -A- through center of vent, one hook on each side.
Making wire hooks -A- Fig. 14
- Using wire hooks, pull vent from instrument panel.
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Fig. 10 Removing and installing rear air outlet (center)
- Carefully pry off trim plate -A- from top using screwdriver.
- Pull back felt liner in storage tray.
- Remove screws -B-.
- Remove rear air outlet -C-.
Fig. 11 Removing and installing instrument panel air outlet (driver's side)
- Remove upper instrument panel air outlet -A- from instrument panel using 2 wire
hooks -B-.
Making wire hooks -B- Fig. 14
- Unhook springs -D-.
- Remove instrument panel air outlet -C- (if equipped) from instrument panel.
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Fig. 12 Removing and installing swivel vents (right and left instrument
panel air outlets)
- Remove instrument panel air outlet.
- Using a screwdriver, carefully pry locking tab.
- Remove swivel vent using wire hook.
Making wire hook Fig. 14
Install in reverse order of removal, noting the following:
- Install swivel vent on correct side.
- Check spring-loaded lock -A- for correct installation position.
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Fig. 13 Removing and installing extraction vent
Note:
Illustration shows vent from the outside, with the bumper cover removed.
- Remove trunk floor mat.
- Lift up left and right trunk floor lining.
- Remove bumper cover.
- Remove vent.
- Check air channels for open passage.
Blocked air channels can result in fogged windows.
- Install vent in reverse order of removal.
Vent flaps at opening must be clean, move freely and close automatically.
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Fig. 14 Making wire hooks (for removing instrument panel air outlets)
- Make wire hooks as shown.
Wire diameter = 3 mm (1/8 in.)
Dimension -X- = 6 mm (1/4 in.)
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Heater and ventilation air ducts, removing and
installing
1 - Footwell air outlet (driver's side)
2 - Seal
3 - Fresh air blower series resistance with fuse -N24-1)
Housing color: orange
---- Mounting bracket for fresh air blower ambient
temperature sensor -G109- 2)
4 - Fresh air blower -V2-
Removing and installing Fig. 7
5 - Heater box
Removing and installing Page 80-18
Assembly Page 80-21
6 - Seal
7 - Footwell air outlet (passenger side)
1)
Manual A/C only
2)
Automatic climate control only
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8 - Defroster hose
9 - Connecting bellows
10 - Rear heater duct
11 - Wiring harness
12 - Support tray for central air flap motor -V70- and
footwell/defroster flap motor -V85- 2)
Removing and installing Page 87-59
13 - Bowden cable for temperature flap1)
Removing and installing Fig. 1
14 - Heater controls1)
Removing and installing Fig. 2
Removing and installing Bowden cables Fig. 3
and Fig. 4
Installing Bowden cable with locking tab broken off
Fig. 5
---- 14a - A/C compressor ON/OFF switch and
recirculating mode button 2)
1)
Manual A/C only
2)
Automatic climate control only
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15 - Bowden cable to center flap 1)
For footwell/defrost and instrument panel air outlets
Removing and installing Fig. 6
16 - Clip nuts
17 - Footwell air duct (center)
18 - Footwell air outlet (rear)
1)
Manual A/C only
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Fig. 1 Removing and installing Bowden cable for temperature flap
- Remove clip -A-.
- Detach Bowden cable and remove.
Fig. 2 Removing and installing heater-A/C controls (manual A/C only)
- Remove heater-A/C control knob.
- Remove trim plate.
- Remove center console Repair Manual, Body Exterior, Interior,Repair Group
70.
- Remove 4 screws -A- and remove heater-A/C controls.
Note:
Replace Bowden cables if they are sticking or binding.
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Fig. 3 Removing Bowden cables at heater-A/C controls (manual A/C only)
- Unlock retaining clip (lower arrow).
- Pull cable upward from retainer (upper arrow).
Fig. 4 Installing Bowden cables at heater-A/C controls (manual A/C only)
A - To center flap (for footwell/defroster and instrument panel air outlets)
B - To temperature flap
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Fig. 5 Installing Bowden cable with locking tab broken off (manual A/C
only)
If locking tab of retainer is broken off:
- Use 4.2 mm x 16 mm (0.165 in. x 0.63 in.) screw and mount in screw hole on
heater controls.
Fig. 6 Removing Bowden cable to center flap for footwell/defroster and
instrument panel air outlets (manual A/C only)
- Remove glove compartment.
- Remove screw -A-.
- Detach Bowden cable and remove.
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Fig. 7 Removing and installing fresh air blower -V2-
- Remove plenum tray.
- Remove heater box Page 80-18 .
- Remove intake duct with fresh air flap.
- Remove locking clip, retaining washer and grommet (assembly -A-).
Install in reverse order of removal noting the following:
- Lubricate mounting tabs -B- with petroleum jelly.
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Heater box, removing and installing
Note:
Heater box can be removed without discharging
A/C system.
Removing
- Remove plenum tray.
- Remove entire windshield wiper motor/linkage
assembly.
- Remove center console, glove box and driver's
side tray Repair Manual, Body Exterior,
Interior, Repair Group 70 .
- Remove heater-A/C controls.
Manual A/C only
- Remove footwell air outlet on driver and
passenger side.
- Remove rubber coupling between heater box
and evaporator housing.
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- Remove defroster hoses and connecting bellows
to rear heater duct.
- Remove connections between heater box and
evaporator housing.
- Loosen cap on coolant expansion tank.
- Disconnect and remove coolant hoses from
heater box.
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- Remove screw -A-.
- Remove tensioning strap.
- Disconnect all connections between vehicle and heater box.
- Attach engine support bridge 10-222 A/1 and heater claw 2075 to lip of heater
box.
- Tighten nut on 10-222 A/1 until heater box is loosened.
- Remove tools.
- Remove heater box.
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Installing
Install in reverse order of removal noting the
following:
- Replace adhesive sealing tape -A-.
- Position ends of sealing tape at top of heater box.
- Check rubber coupling between heater box and evaporator for leaks.
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Heater box, disassembling and assembling
Note:
Seal off area -A- with silicon rubber compound (commercially
available) when assembling the two housing halves.
The illustration shows two different heater box component
arrangements:
Components marked with 1) are used with automatic
climate control only
Components marked with 2) are used with manual A/C
only
1 - Control flap for instrument panel air outlets
2 - Screw
3 - Locking clips
4 - Lever for footwell/defroster control flap 1)
Red
1)
Automatic climate control only
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5 - Turbulence flap retaining assembly
Installed position Fig. 1
6 - Fresh air blower series resistance with fuse -N24-2)
Housing color: orange
6a - Mounting bracket for fresh air blower ambient
temperature sensor -G109- 1)
7 - Snap ring
8 - Washer
9 - Grommet
1)
Automatic climate control only
2)
Manual A/C only
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10 - Left housing half
Aligning flaps Fig. 2
11 - Retaining clips
7x on perimeter
12 - Mounting tabs for fresh air blower
Coat lightly with petroleum jelly
13 - Fresh air blower -V2-
Removing and installing Fig. 7
14 - Heater core
Applying self-adhesive seal Fig. 3
Sealing left housing half Fig. 4
15 - Temperature flap
In front of heater core
16 - Temperature flap
Behind heater core
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17 - Seal
18 - Screw
19 - Footwell/defroster flap 2)
19a - Footwell/defroster flap 1)
20 - Stop pins2)
21 - Adhesive tabs
22 - Turbulence flap
23 - Sealing cord
Install around entire left housing half
24 - Right housing half
25 - Intake duct
26 - Bearing
27 - Temperature flap lever
Assembling Fig. 5
28 - Retaining washers
1)
Automatic climate control only
2)
Manual A/C only
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29 - Locking clip 1)
30 - Center flap lever 2)
For footwell/defroster and instrument panel air
outlets
31 - Flap lever 1)
For instrument panel air outlets
Blue
32 - Screw
1)
Automatic climate control only
2)
Manual A/C only
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Fig. 1 Turbulence flap attachment
- Install turbulence flap retaining assembly (washer, felt ring, and locking clip -A-).
Fig. 2 Aligning flaps in left housing half
- Using aligning tool -2076 A-, install flaps -A-, -B- and -C-, left to right, as shown.
Note:
On vehicles with automatic climate control, install flap -B- turned 180 (1/2 -turn).
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Fig. 3 Applying self-adhesive seal to heater core
- Install seal (as shown) so there are no gaps around perimeter of heater core.
Fig. 4 Sealing heater core outlet (at left housing half)
- After installing heater core, fill area -A- with silicon rubber sealant (commercially
available).
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Fig. 5 Assembling temperature flap levers
- Assemble temperature flap levers as shown.
- Install assembly on heater box.
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