Housing Assembly HVAC: Service and Repair

Removing And Installing Heating/fresh Air Unit

Technical values







Preliminary work

Preliminary work for heating/fresh air unit
1. Drain refrigerant.
2. Drain engine coolant.
3. Remove dashboard.
4. Remove tunnel support.
5. Remove passenger's airbag unit.
6. Remove battery.
7. Remove right plenum panel cover.
8. Remove heat exchanger.

Removing heating/fresh air unit


INFORMATION: Make sure not to damage the insulation of the main wiring harness.







1. Immediately seal the openings of air-conditioning lines with suitable plugs.







2. Unscrew fastening screw -1- for refrigerant line -C- and open the pressure line.







3. Unscrew fastening screws -2- and remove expansion valve.







4. Unscrew the fastening nuts -6- for the heater/air-conditioning unit in the area of the plenum panel/firewall.







5. Unscrew fastening screw -3- for securing holder of the heater/air-conditioning unit to right side of dashboard bracket (next to A-pillar).







6. Unscrew fastening screw -4- for securing heater/air-conditioning unit to right side of dashboard bracket (passenger's side).







7. Unscrew the two fastening screws -5- for dashboard bracket to right side of body.







8. Unclip holder for electric harness with a screwdriver from right side of dashboard bracket.







9. Now pull dashboard bracket a few centimeters forward on the right side.







10. Pull out cotter pin -A- for holder of the heater/air-conditioning unit.







11. Turn holder -B- for heater/air-conditioning unit by 90° and pull up and out.







12. Lay down the air conditioner, release clamp for water drain hose -C- and pull off the water drain hose from the heater/air-conditioning unit.







13. Carefully lift heater/air-conditioning unit forward with a screwdriver under the right side of the dashboard bracket.







14. Release lower plug connection on heater/air-conditioning unit -a- and unplug.







15. Release upper plug connection on heater/air-conditioning unit -a- and unplug.







16. Cut tie-wraps of electric line (vehicle wire harness to heater/air-conditioning unit wire harness) with side cutters. Remove vehicle wire harness.







17. Pull air conditioner forward on the right side, unscrew fastening screw -7- for B+ line holder and remove holder for heater/air-conditioning unit.







18. Pull/push heater/air-conditioning unit as far as possible in direction of passenger's seat.







19. Remove heater/air-conditioning unit from passenger compartment via passenger's door.

Installing heating/fresh air unit

INFORMATION:
- Do not remove the plugs until just before installing the expansion valve.
- Check the condition of foam parts for damage; if in doubt replace.







1. Insert heater/air-conditioning unit in the vehicle over the passenger's side.







2. Lift heater/air-conditioning unit over the centre console and position under dashboard bracket.







3. Position holder for the B+ line on the heater/air-conditioning unit and tighten with the fastening screw -7-.
Tightening torque: 1.7 Nm (1.5 ftlb.)







4. Lay electric line from vehicle wire harness to heater/air-conditioning unit wire harness and fix with a tie-wrap.







5. Connect upper electric plug connection at heater/air-conditioning unit until it is felt to engage.







6. Connect upper electric plug connection at heater/air-conditioning unit until it is felt to engage.







7. Check water drain hose for damage; if drain hose shows no sign of damage, connect hose to the drain on heater/air-conditioning unit and fix with the clamp -C-.







8. Push heater/air-conditioning unit into position under right side of dashboard bracket in the direction of firewall.







9. Guide holder -B- for the heater/air-conditioning unit over the dashboard bracket, push through the mounting of the heater/air-conditioning unit and turn through 90°.







10. Fix holder for heater/air-conditioning unit with cotter pin -A-.







11. Push dashboard bracket forwards while lifting the heater/air-conditioning unit and taking care that no electric lines get trapped.







12. Screw down dashboard bracket with the two fastening screws -5-.
Tightening torque: 23 Nm (17 ftlb.)







13. Clip in the plastic holders for the electric main wire harness to the dashboard bracket.







14. Secure dashboard bracket with the fastening screw -4-.
Tightening torque: 9.7 Nm (7.0 ftlb.)







15. Screw down holder of heater/air-conditioning unit with the fastening screw -3-.
Tightening torque: 3.5 Nm (2.5 ftlb.)







16. Slide the fastening bolts of the heater/air-conditioning unit through the firewall lid and tighten with the three fastening nuts -6-.
Tightening torque: 9.7 Nm (7.0 ftlb.)


INFORMATION:
- Do not remove the plugs until just before installing the expansion valve.
- Check the condition of foam parts for damage; if in doubt replace.







17. Install expansion valve and tighten with the two fastening screws -2- , replace sealing rings for refrigerant lines and wet them with refrigerant.
Tightening torque: 9 Nm (6.5 ftlb.)







18. Replace sealing rings for refrigerant lines and wet with refrigerant. Position refrigerant line and tighten with fastening screw -1-. - M8: 14 Nm (10.5 ftlb.)

Subsequent work

Subsequent work for heater/air-conditioning unit
1. Install heat exchanger.
2. Install passenger's airbag unit.
3. Install tunnel support.
4. Install dashboard.
5. Install and connect the battery.
6. Fill in refrigerant.
7. Top up engine coolant.
8. Install right cover for plenum panel.