Removing and Installing/Replacing Heater

64 11 205 - Removing and installing/replacing heater





Warning!
Avoid contact with refrigerant and refrigerant oil.
Follow safety instructions for handling refrigerant R 134a Instructions for Handling Refrigerant R 134a.
Follow safety instructions for handling refrigerant oil Instructions for Handling Refrigerant Oil (for Refrigerant R 134a).
Follow instructions for working on cooling system Instructions for Working on Cooling System!





Important!
Risk of damage!
Restart engine only when A/C system has been correctly filled.
Comply with notes and instructions 61 00 ... Notes on Handling Optical Fibers on handling optical waveguides.
If A/C system is opened for more than 24 hours: Replacing drier insert for A/C system Removing and Installing/Replacing Condenser for A/C System





Necessary preliminary tasks:
- Drawing off, evacuating and filling the A/C system Drawing off, Evacuating and Filling A/C System (R 134a) are not included in the time value given for this work operation
- Disconnect battery negative lead Disconnecting and Connecting Battery Negative Lead
- If necessary, remove acoustic cover
- Remove center of assembly compartment bulkhead 51 71 085 Removing and installing center of assembly compartment bulkhead
- Remove fresh air duct Removing and Installing/Replacing Left or Right Fresh-Air Duct (Automatic A/C High) on left and right
- Remove trim 51 45 030 Removing and Installing Instrument Panel Trim on instrument panel





Gently pull out locks of quick-release couplings (1) and detach coolant hoses (2).

Important!
Carefully blow through aluminum triple pipe to remove remaining coolant from heater element.

Installation Note:
Vent cooling system and check for leaks.

Release screws (3) and detach refrigerant lines (4).

Installation Note:
Replace sealing rings.
Tightening torque 64 52 1AZ [1][2]Specifications.





- Release steering spindle lower section Removing and Installing/Replacing Lower Section of Steering Spindle





Unscrew nuts (1).

Installation Note:
Check that grommet (2) is correctly seated





- Disconnect all necessary cable ties on support tube
- Release wiring harnesses/cable ducts and lay to one side
- If necessary, remove control units/disconnect plug connections

Installation Note:
Make sure wiring harnesses/cable ducts are correctly secured and laid.





Release retainers and unclip defroster vent (1) at catches.
Carefully lift out defroster vent (1).
Unfasten screws (2).

Installation Note:
Tightening torque 51 71 12AZ Specifications.

Unscrew nuts (3).





Release screws (1).
Lay fuse-carrier (2) to one side.
Unscrew nuts (3).





Unscrew nuts (1).
Detach support tube (2) and remove from vehicle with assistance of a second person.





- Remove soundproofing on left and right from heater
- Disconnect plug connections
- If necessary, release wiring harness and lay to one side

Installation Note:
Make sure soundproofing on left and right is correctly seated.
Ensure correct wiring harness routing.





Unscrew nuts (1).
Remove heater (2) in direction of arrow.

Installation Note:
Make sure heater (2) is correctly seated.





Installation Note:
Make sure condensate drain (1) and intermediate piece (2) on left and right are correctly seated.





After installation:
- Bleeding cooling system and checking for water leaks
- Evacuate and fill A/C system Drawing off, Evacuating and Filling A/C System (R 134a)