A/c Heater Systems - E36: Removal & Installation BMW 3 series E46

REMOVAL & INSTALLATION

Insert a feeler gauge between on-board computer display frame and lower shelf to push back locking lever(s). Carefully pry out on-board computer. Disconnect wiring harness and remove on-board computer. Pull out A/C-heater control panel. Disconnect wiring harness. To install, reverse removal procedure.

1. Discharge A/C system, using approved refrigerant recovery/recycling equipment. Pull rubber sealing strip from cowl/firewall. Remove air intake grille. Remove screws attaching wiring harness to heater cover, and pull wiring out of the way.
2. Remove air intake duct bolts, and remove air intake duct. Remove engine covers. Drain cooling system. Disconnect heater hoses at heater core flange. Remove heater brackets from firewall. Disconnect and plug refrigerant lines.
3. Remove air outlet grilles from instrument panel. Loosen clips and remove glove box. Remove trim from "A" pillars. Remove trim panels from right and left sides of instrument panel.
4. Lower steering column. See «STEERING COLUMN»(ref-149611-S35126326162002101600000). Remove 3 instrument cluster screws. Carefully pull out instrument cluster. Raise wiring harness connector levers on back of instrument cluster and disconnect wiring harness. Remove instrument cluster.
5. Remove shift lever dust cover. Pull out center console storage unit and ashtray. Remove hazard light warning switch and rear ashtray. Remove screws and parking brake lever console. Remove screws and lift out center console. (Scheme 6)and (Scheme 7).
6. Remove bolts from ends of instrument panel. Ensure all wiring harnesses are disconnected. Carefully remove instrument panel. (Scheme 8)and (Scheme 9). Pry out control unit, and disconnect it from wiring harness.
7. Cut wiring harness straps and remove reinforcement pipe for steering column. Cut wiring harness strap and disconnect wiring harness from A/C-heater unit. Remove bolts and A/C-heater unit.
8. To install, reverse removal procedure. Ensure wiring harnesses are not pinched during installation. Replace heater core flange "O" rings. It may be necessary to recode instrument cluster (dealership procedure only). Check A/C-heater system for proper operation.

Scheme 6

Scheme 7

Scheme 8

Scheme 9

Removal & Installation (Main)

1. Disconnect negative battery cable. Pull rubber sealing strip from cowl/firewall. Remove air intake grille. Remove screws attaching wiring harness to heater cover, and pull wiring out of way.
2. Remove air intake duct bolts, and remove air intake duct. Remove engine covers. Remove wiring harness cover and disconnect wiring harnesses from control units on firewall.
3. Loosen clips and remove blower motor cover. (Scheme 10) Disconnect wiring harness connectors from blower motor. Disengage clips and lift left flap upper section up. Remove blower motor wheels at brace and carefully lift out blower motor. (Scheme 11) To install, reverse removal procedure. Ensure all seals are installed correctly.

Scheme 10

Scheme 11

Removal & Installation (Rear - Convertible)

Lower top to full down position. Remove rear seat cushion and rear seat back. Remove 4 screws from cover in center of vehicle. Disconnect electrical connector and remove screws attaching rear blower motor to vehicle. Remove rear blower motor from opening by lowering it down and rolling it to the left to clear outlets. Disassemble rear blower motor case to replace blower motor.

1. Disconnect negative battery cable. Discharge A/C system, using approved refrigerant recovery/recycling equipment. Remove engine splash shield. Disconnect compressor clutch electrical connectors.
2. Loosen A/C compressor belt tensioner bolt(s) to relieve belt tension, and remove A/C compressor belt. Remove refrigerant hose couplings. Plug refrigerant lines. Remove compressor bolts, and remove A/C compressor. To install, reverse removal procedure. Check compressor oil level. Evacuate, charge, and leak test A/C system.

1. Dust/pollen filter is located in passenger compartment, in front of center console, below center of windshield. Remove glove box and lay aside. Remove right kick panel. Detach control module box from retaining slots and lay aside. Unclip passenger's side air duct.
2. Locate dust/pollen filter cover next to firewall. Turn dust/pollen filter housing cover cam lock about 45 degrees and open cover. Reach in small opening and slide out dust pollen filter. Dust/pollen filter may have to be folded or bent to remove. To install, reverse removal procedure. Ensure new filter seals and is not bent or kinked in housing.

1. Disconnect negative battery cable. Discharge A/C system, using approved refrigerant recovery/recycling equipment. Disconnect A/C hoses for evaporator core (in engine compartment).
2. Remove lower instrument panel covers. Disconnect A/C pipes from firewall to evaporator core by removing the A/C pipe holder screws and sliding pipes upward with pressure plate. (Scheme 12)
3. Remove evaporator cover from evaporator case. Remove evaporator by sliding sideways off of case. Remove expansion valve from evaporator core. Drain refrigerant oil from evaporator and measure amount.
4. To install, reverse removal procedure. Replace oil in evaporator with same the amount as was removed. Replace all "O" rings and coat them with refrigerant oil before installation. Evacuate, charge, and leak test A/C system.

Scheme 12

1. Pull off rubber air intake duct seal. Pry out plastic grille from air intake cowl. Remove 2 screws under plastic grille. Remove 2 air collector screws. Pull out air collector. NOTE: Air collector is difficult to pull out.
2. Remove engine covers. Remove water flange nut at firewall. Lay water flange and hoses aside. Blow out coolant from heater core with compressed air. Remove flange stud. (Scheme 13)
3. From inside vehicle, remove bolts from heater unit located under left side of instrument panel, next to console, and above gas pedal. (Scheme 14) Pry off left instrument panel lower trim. (Scheme 15) Remove left knee bolster. Remove lower steering column cover. Remove double pipe bolt. (Scheme 16) Remove double pipe. Remove 2 heater core screws. Slide out heater core. (Scheme 17) To install, reverse removal procedure. Fill cooling system and check for leaks.

Scheme 13

Scheme 14

Scheme 15

Scheme 16

Scheme 17

Remove A/C-heater control unit. See A/C-HEATER CONTROL PANEL . Disconnect interior temperature sensor and fan connector on A/C-heater control unit. To install, reverse removal procedure.

1. Disable air bag system. See AIR BAG SYSTEM SAFETY article in GENERAL SERVICING. Ensure steering wheel is in straight-ahead position. Unlock bayonet mount at base of steering column by turning it counterclockwise.
2. Remove screw and lower cover on steering column. Remove bolt from steering column universal joint. Remove anti-tamper screws, and lower steering column. To install, reverse removal procedure. Replace anti-tamper screws.