Housing Assembly HVAC: Service and Repair
WM 851519 Removing and installing heating/fresh air unit
Preliminary work
1. Disconnect the battery. -> 2X00IN Work instructions after disconnecting the battery - section on "Disconnecting" 2X00IN Work instructions after disconnecting the battery
2. Remove the dashboard bracket. -> 516819 Removing and installing dashboard bracket - section on "Removing" 516819 Removing and Installing Dashboard Support
3. Remove wiper linkage. -> 921919 Removing and installing wiper linkage - section on "Removing" Service and Repair
4. Drain refrigerant. -> 870317 Draining and filling refrigerant - section on "Draining" Service and Repair
5. Drain coolant. -> 193817 Draining and filling coolant - section on "Draining" Service and Repair
6. Remove front centre console. -> 681719 Removing and installing centre console - section on "Removing" 681719 Removing and installing centre console
Removing heating/fresh air unit
Installation position
Information
The heat exchanger connection must be closed off using suitable stoppers once the cooling water hoses have been removed.
1. Disconnect heat exchanger return hose. -> 803219 Removing and installing heat exchanger return hose - section on "Removing" 803219 Removing and installing heat exchanger return hose
2. Disconnect heat exchanger supply hose. -> 803019 Removing and installing heat exchanger supply hose - section on "Removing" 803019 Removing and installing heat exchanger supply hose
3. Disconnect refrigerant hoses at the expansion valve. -> 877019 Removing and installing expansion valve - section on "Removing" Service and Repair
4. Pull connections for condensed water drain tubes -1- at the left and right out of the body tunnel -arrow-.
Pulling out condensed water drain tubes
5. Release and pull off electric plug connection on the blower regulator -1-.
Pulling off connector for heating/fresh air unit
6. Release and pull off electric plug connection for servo motors -1-.
Disconnecting connector for servo motors
7. Pull the rubber straps -1- out of the anchoring device -2- ( -arrow- ).
Pulling off rubber straps
8. Gently pull the connection pieces -2- for the cooling and heating media at the heating/fresh air unit towards the passenger compartment -arrow- and out of the rubber sleeves -1- in the firewall cover.
Pulling off heating/fresh air unit
9. Remove the heating/fresh air unit by pulling it towards the passenger compartment.
Installing heating/fresh air unit
Information
The seals on the refrigerant connections must be checked for damage. If in doubt, replace the seals.
1. Place the cut-out in the insulating mat on the front passenger side -1- over the air intake connection piece -2- on the heating/fresh air unit.
Placing insulating mat over air intake connection piece
2. Install the heating/fresh air unit.
Information
Mounting pegs, guides and rubber sleeves must be treated with sliding compound before installing the heating/fresh air unit.
2.1. Insert mounting pegs of the heating/fresh air unit into the guides -1-.
2.2. Insert the connection pieces on the heating/fresh air unit for the cooling and heating media into the rubber sleeves -2- in the firewall cover.
Fitting unit in firewall
3. Check that the rubber sleeves -1- engage in the mounting grooves on the connection pieces -2- of the cooling and heating media. If not, re-adjust them.
Fitting rubber sleeves into groove on connection pieces
4. Pull out the rubber straps -1- behind the heating/fresh air unit and engage them in the anchoring device -2- for the heating/fresh air unit -arrow-.
Hooking in rubber straps
5. Plug in electric plug connection -1- for the heating/fresh air unit until it engages securely.
Inserting connector
6. Plug in electric plug connection for servo motors -1- until it engages securely.
Plugging in connector for servo motors
7. Press connections for condensed water drain tubes -1- at the left and right into the fittings on the body tunnel -arrow-.
Installing condensed water drain tubes
8. Secure the refrigerant hoses at the expansion valve. -> 877019 Removing and installing expansion valve - section on "Installing" Service and Repair
9. Secure the heat exchanger return hose. -> 803219 Removing and installing heat exchanger return hose - section on "Installing" 803219 Removing and installing heat exchanger return hose
10. Secure the heat exchanger supply hose. -> 803019 Removing and installing heat exchanger supply hose - section on "Installing" 803019 Removing and installing heat exchanger supply hose
Subsequent work
1. Fill in coolant. -> 193817 Draining and filling coolant - section on "Filling" Service and Repair
2. Bleed the cooling system. -> 190101 Checking the cooling system - section on "Bleeding" Testing and Inspection
3. Fill in refrigerant. -> 870317 Draining and filling refrigerant - section on "Filling" Service and Repair
4. Install wiper linkage. -> 921919 Removing and installing wiper linkage - section on "Installing" Service and Repair
5. Install front centre console. -> 681719 Removing and installing centre console - section on "Installing" 681719 Removing and installing centre console
6. Install dashboard support. -> 516819 Removing and installing dashboard support - section on "Installing" 516819 Removing and Installing Dashboard Support
7. Connect the battery. -> 2X00IN Work instructions after disconnecting the battery - section on "Connecting" 2X00IN Work instructions after disconnecting the battery