Automatic A/c-Heater Systems: Removal & Installation Audi A4 B5 facelift

REMOVAL & INSTALLATION

1. Discharge A/C system, using approved refrigerant recovery/recycling equipment. Remove front bumper/grille assembly. Remove front noise insulation panel under engine.
2. Mark direction of drive belt. Loosen drive belt tensioner (2 bolts) and remove drive belt. Remove bolts and A/C compressor. (Scheme 7) Remove and plug high and low-pressure lines from A/C compressor. Discard "O" rings.
3. To install, reverse removal procedure. Use NEW "O" rings lubricated with clean refrigerant PAG oil before installing. Tighten connections to specification. See «TORQUE SPECIFICATIONS»(ref-12058-S18315709622000120700000). Evacuate and charge A/C system.

Scheme 7

Removal

1. Ensure wheels are in straight-ahead position. Move power seats to rearmost position. Obtain radio anti-theft protection code. Disable air bag system. See AIR BAG SYSTEM SAFETY article in GENERAL SERVICING. Remove coolant expansion tank cap slowly to release cooling system pressure.
2. Clamp coolant hoses, and disconnect hoses from heater core. Place container under heater core connections, and apply compressed air through inlet hole to blow coolant out of heater core. Remove boot and bolt from heater core.
3. Discharge A/C system, using approved refrigerant recovery/recycling equipment. Remove bolt and refrigerant lines from evaporator. Plug evaporator connections to prevent contamination. Remove boot from evaporator.
4. Remove glove box/knee bar assembly. Unclip cap for instrument panel. Remove bolts from driver's side stowage compartment/knee bar assembly. Disengage stowage compartment from clips, and remove stowage compartment. Remove center console. See «CENTER CONSOLE»(ref-12058-S10637243952000120700000). Remove pedal assembly mounting bolt from instrument panel. (Scheme 8)
5. Using T30 Torx bit, remove screws securing air bag module to steering wheel. Remove air bag module, and disconnect electrical connector. Remove steering wheel. Remove steering column from steering gear, and secure with wire. (Scheme 8)
6. Remove auxiliary relay panel/auxiliary fuse holder (located in bottom left footwell), and secure aside. Disconnect instrument panel electrical connectors. Remove instrument panel outer skin.
7. Remove passenger's side instrument panel support (at instrument panel/center console support bracket). Loosen driver's side instrument panel support (as the upper mounting bolt to the A/C-heater assembly cannot be removed).
8. Remove footwell air outlet. Disconnect all electrical connectors between A/C-heater assembly and instrument panel. Mark instrument panel-to-A/C-heater assembly screws/bolts for installation reference. Remove screw/bolts, and separate instrument panel from A/C-heater assembly.

Installation

1. To install, reverse removal procedure. Replace all damaged A/C-heater seals and cable tie wraps. Replace inlet/outlet "O" rings. Ensure refrigerant lines fit into evaporator without binding.
2. Ensure evaporator drain valve is correctly installed. Evacuate and charge A/C system. Tighten nuts and bolts to specification. See «TORQUE SPECIFICATIONS»(ref-12058-S18315709622000120700000) .

Scheme 8

1. Obtain radio anti-theft protection code. Disconnect negative battery cable. Remove radio. Remove screws and center instrument panel trim. Remove screws and A/C-heater control panel. Push back connector locks, and disconnect electrical connectors.
2. To install, reverse removal procedure. Ensure shaped hose to instrument panel interior temperature sensor is routed properly and not kinked. Tighten screws to specification. See «TORQUE SPECIFICATIONS»(ref-12058-S18315709622000120700000) .

1. Discharge A/C system, using approved refrigerant recovery/recycling equipment. Remove front bumper/grille assembly. Remove bolt and nuts from bracket. Remove refrigerant line from right side of accumulator. Remove accumulator and bracket assembly. Remove refrigerant line from left side of accumulator. Remove accumulator from bracket and insulating sleeve.
2. To install, reverse removal procedure. Use NEW "O" rings. Tighten refrigerant lines to specification. See «TORQUE SPECIFICATIONS»(ref-12058-S18315709622000120700000) . Align spring with mounting hole on bracket and mark on refrigerant hose.

Removal (Airflow Flap Motor)

1. Disable air bag system. See AIR BAG SYSTEM SAFETY article in GENERAL SERVICING. Remove glove box. Disconnect electrical connector from motor. Remove bolts attaching motor to A/C-heater assembly. Detach strap from bracket of A/C-heater assembly. Remove airflow flap motor.
2. To install, reverse removal procedure. Ensure that metal lever moves the airflow flap and is inserted into closed guide groove. Ensure that plastic lever moves the fresh/recirculated air flap and only assumes an open guide groove position when in recirculated air mode.

Removal (Central & Temperature Regulator Flap Motors)

1. Remove front section of center console. See «CENTER CONSOLE»(ref-12058-S10637243952000120700000). Loosen floor outlet from right instrument panel support.
2. Remove 3 bolts from central air flap motor. Disconnect electrical connector from motor. Release Blue lever, and remove central air flap motor. (Scheme 9)
3. Remove 3 bolts from temperature regulator flap motor. Disconnect electrical connector from motor. Release Red lever, and remove temperature regulator flap motor. (Scheme 10) To install, reverse removal procedure.

Scheme 9

Scheme 10

Removal (Footwell/Defroster Flap Motor)

Remove panel under left side of instrument panel. Remove 2 left instrument panel support bolts. Remove floor outlet. Disconnect electrical connector from motor. Remove lower strap bolt. Using screwdriver, unhook lower strap of bracket. Release White lever. Remove the footwell/defroster flap motor. (Scheme 11) To install, reverse removal procedure.

Scheme 11

Removal & Installation (Rear)

1. Pry out locking pin, and remove parking brake lever trim. Unclip cover and remove bolts. (Scheme 12) Remove ashtray. Remove screw/nuts and center armrest.
2. Remove nut from behind parking brake lever. Apply parking brakes. Raise console slightly, and disconnect from front center console. Remove rear center console. Disconnect electrical connector.
3. To install, reverse removal procedure. Tighten nuts and bolts to specification. See «TORQUE SPECIFICATIONS»(ref-12058-S18315709622000120700000).

Removal & Installation (Front)

1. Remove rear portion of center console. See «CENTER CONSOLE (REAR)»(ref-12058-S32725701562000120700000). Remove 4 front center console mounting bolts. Remove A/C-heater control panel. See «A/C-HEATER CONTROL PANEL»(ref-12058-S11941255612000120700000).
2. Unclip cover, and remove nuts and bolts. Disconnect and pull front center console rearward to remove from vehicle.
3. To install, reverse removal procedure. Ensure center console is inserted into clip. (Scheme 13) Tighten nuts and bolts to specification. See «TORQUE SPECIFICATIONS»(ref-12058-S18315709622000120700000).

Scheme 12

Scheme 13

Remove radio (for center outlet temperature sensor) or panel under left side of instrument panel (for floor outlet temperature sensor). Disconnect electrical connector from sensor(s). Turn sensor 90 degrees and remove. To install, reverse removal procedure.

Remove right cowl air plenum cover. Remove water guide. Remove dust/pollen filter. (Scheme 7) To install, reverse removal procedure.

1. Remove A/C-heater assembly. See «A/C-HEATER ASSEMBLY»(ref-12058-S31337385702000120700000). Remove heater core. See «HEATER CORE»(ref-12058-S37691756182000120700000). Remove fresh air blower. (Scheme 14)
2. Remove airflow flap motor. (Scheme 15) Remove top part of evaporator housing and gasket. Remove evaporator.

1. To install, reverse removal procedure. Ensure foam gasket around evaporator core has a gap along bottom (to allow condensation drainage). Use foam gasket to seal refrigerant lines at air distribution housing halves.
2. Check for codes. See «RETRIEVING & CLEARING DIAGNOSTIC TROUBLE CODES»(ref-12058-S00600530252000120700000) under SELF-DIAGNOSTICS. Test airflow flap motor. See «OUTPUT DIAGNOSTIC TEST MODE»(ref-12058-S18601589982000120700000) under SELF-DIAGNOSTICS. See «AIR/TEMPERATURE DISTRIBUTION FLAP MOTORS & SENSORS»(ref-12058-S11967045492000120700000) under SYSTEM TESTS.

Scheme 14

1. Disable air bag system. See AIR BAG SYSTEM SAFETY article in GENERAL SERVICING. Remove glove box and glove box mounting. Remove mounting for passenger air bag. Disconnect electrical connector from fresh air blower.
2. Remove 3 screws and fresh air blower from A/C-heater assembly. (Scheme 15) Depress locking tabs and separate fresh air blower from mounting plate. Disconnect electrical connectors. To install, reverse removal procedure.

Remove fresh air blower. See FRESH AIR BLOWER . Remove fresh air blower from mounting plate. Remove screws and fresh air blower control module from mounting plate. To install, reverse removal procedure.

Disable air bag system. See AIR BAG SYSTEM SAFETY article in GENERAL SERVICING. Remove glove box. Locate fresh air intake duct temperature sensor behind fresh air blower motor. Reach in between A/C-heater assembly and bulkhead and turn sensor 90 degrees clockwise. To install, reverse removal procedure. After sensor installation, check for codes. See RETRIEVING & CLEARING DIAGNOSTIC TROUBLE CODES under SELF-DIAGNOSTICS.

1. Remove A/C-heater assembly and instrument panel. See «A/C-HEATER ASSEMBLY»(ref-12058-S31337385702000120700000) . Press catches on sides of heater core, and remove heater core from housing.
2. Apply self-adhesive seals to heater core. Ensure no gaps exist between seals and heater core. To install, reverse removal procedure. If heater core does not engage in heater housing, attach with 2 screws.

Scheme 15

1. Discharge A/C system, using approved refrigerant recovery/recycling equipment. Remove refrigerant line clamp bolt. Loosen refrigerant line clamp and remove lines from evaporator.
2. Using needle nose pliers, remove restrictor (orifice tube) from evaporator inlet. To install, reverse removal procedure. Use NEW "O" rings. Insert orifice tube with arrow pointing toward evaporator, and push until firmly seated.