Overhaul

DISASSEMBLY
1. Remove the HVAC housing from the vehicle and place it on the workbench. Refer to: Heating and Air Conditioning, Housing Assembly HVAC, Service and Repair, Procedures, HVAC Housing Removal and Installation, Removal and Replacement

2. Unplug the vacuum harness connectors from the floor door actuator and, if the unit is so equipped, the recirculation door actuator.
3. Disengage the vacuum harness from any routing clips located on the lower half of the HVAC housing.
4. Disengage the HVAC wire harness connector and and the blower motor relay wire harness connector push-in retainers from their mounting holes on the HVAC housing.
5. Remove the blower motor and blower wheel unit from the HVAC housing. Refer to: Heating and Air Conditioning, Blower Motor, Service and Repair,

6. Carefully remove the foam seal from the flange around the blower motor opening in the HVAC housing. If the seal is deformed or damaged it must be replaced.

Fig.46 HVAC Housing Disassembly:

7. Pull the vacuum supply line and connector through the foam seal on the heater core and evaporator coil tube mounting flange of the HVAC housing.
8. If the unit is equipped with air conditioning, remove the screw that secures the clamp to the evaporator coil tubes and remove the clamp.
9. Carefully remove the foam seal from the heater core and evaporator coil tube mounting flange of the HVAC housing. If the seal is deformed or damaged it must be replaced.
10. Use a screwdriver to pry off the two snap clips that help secure the upper and lower HVAC housing halves together.
11. Remove the 14 screws that secure the upper and lower HVAC housing halves together.
12. Carefully separate the upper HVAC housing from the lower half.

ASSEMBLY

Fig.47 HVAC Housing Assembly:

1. Assemble the upper HVAC housing half to the lower half. During assembly, be certain of the following.
a. That each of the mode door pivot shaft ends are properly engaged in its pivot hole.
b. That the blower motor venturi ring is properly indexed and installed.
c. If the unit is equipped with air conditioning, that the evaporator coil tube rubber seal is properly positioned in the grooves in both the upper and lower HVAC housing halves.
2. Install the 14 screws and two snap clips that secure the upper and lower HVAC housing halves to each other. Tighten the screws to 2.2 Nm (20 in.lbs.).
3. Install the blower motor and wheel unit in the HVAC housing. Refer to: Heating and Air Conditioning, Blower Motor, Service and Repair,

4. Install the foam seals on the flanges around the blower motor opening and the heater core and evaporator coil tube mounting flange of the HVAC housing.
5. Insert the vacuum supply line and connector through the foam seal on the heater core and evaporator coil tube mounting flange of the HVAC housing.
6. If the unit is equipped with air conditioning, reinstall the evaporator coil tube clamp. Tighten the mounting screw to 2.2 Nm (20 in. lbs.).
7. Engage the HVAC wire harness connector and the blower motor relay wire harness connector push in retainers with their mounting holes in the HVAC housing.
8. Engage the vacuum harness to the routing clips and plug in the vacuum harness connector at the floor door actuator and, if the unit is so equipped, at the recirculation air door actuator. Refer to: Heating and Air Conditioning, Housing Assembly HVAC, Service and Repair, Procedures, HVAC Housing Removal and Installation, Removal and Replacement