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Housing Assembly HVAC: Service and Repair






This procedure may require the removal and installation of the instrument panel and/or some its components. For these procedures. Refer to: Body and Frame, Interior Trim, Dashboard/Instrument Panel, Service and Repair, Instrument Panel Assembly Replacement, Instrument Panel Assembly Replacement

WARNING: ON VEHICLES EQUIPPED WITH AIR-BAGS,REFER TO PASSIVE RESTRAINT SYSTEMS BEFORE ATTEMPTING ANY STEERING WHEEL, STEERING COLUMN, OR INSTRUMENT PANEL COMPONENT DIAGNOSIS OR SERVICE. FAILURE TO TAKE THE PROPER PRECAUTIONS. COULD RESULT IN ACCIDENTAL AIR- BAG DEPLOYMENT AND POSSIBLE PERSONAL INJURY.

HEATER-A/C HOUSING
The heater-A/C housing assembly must be removed from the vehicle and disassembled for service access of the heater core, evaporator coil, and each of the various mode control doors.

REMOVAL
1. Disconnect and isolate the battery negative cable.
2. Remove the instrument panel.Refer to: Body and Frame, Interior Trim, Dashboard/Instrument Panel, Service and Repair, Instrument Panel Assembly Replacement, Instrument Panel Assembly Replacement

3. If the vehicle is not equipped with air conditioning, go to Step 6. If the vehicle is equipped with air conditioning, recover the refrigerant from the refrigerant system, please refer to: Heating and Air Conditioning, Service and Repair, Refrigerant Recovery, Refrigerant Recovery

4. Disconnect the liquid line refrigerant line fitting from the evaporator inlet tube. Install plugs in, or tape over all of the opened refrigerant line fittings.
5. Disconnect the accumulator inlet tube refrigerant line fitting from the evaporator outlet tube.Install plugs in, or tape over all of the opened refrigerant line fittings.
6. Drain the engine cooling system.
7. Disconnect the heater hoses from the heater-tubes.Install plugs in, or tape over the opened core tubes.
8. Remove the Powertrain Control Module (PCM) from the dash panel and set it aside, but do not unplug the PCM wire harness connectors.
9. Remove the nuts from the heater-A/C housing mounting studs on the engine compartment side of the dash panel.

Fig 47 Heater-A/C Housing:






10. Remove the nuts that secure the heater A/C housing to the mounting studs on the passenger compartment side of the dash panel
11. Pull the heater A/C housing rearward far enough for the mounting studs and the evaporator condensate drain tube to clear the dash panel holes.
12. Remove the heater A/C housing from the vehicle.

DISASSEMBLY

1. Place the heater-A/C housing upside down on a work bench.
2. Remove the screw that secures the floor duct to the bottom of the heater A/C housing and slide the floor duct off of the center heat duct adaptor.
3. Unsnap the center heat duct adaptor from the bottom of the heater-A/C housing and remove the screw that was hidden by the adaptor.
4. Remove the remaining screws on the bottom of the heater-A/C housing that secure the two housing halves together.
5. Place the heater-A/C housing right side up on the work bench.
6. Separate the top half of the heater-A/C housing from the bottom half and set it aside.

ASSEMBLY

1. Position the top half of the heater-A/C housing over the bottom half� Be certain that the mode door pivot pins are properly inserted in their pivot holes.
2. Place the heater-A/C housing upside down on the work bench.
3. Install and tighten the screws on the bottom of the heater-A/C housing that secure the two housing halves together. Tighten the screws to 2.2 Nm (20 in. lbs.).
4. Snap the center heat duct adaptor onto the bottom of the heater-A/C housing.
5. Slide the floor duct onto the center heat duct adaptor and secure it with a screw to the bottom of the heater-A/C housing. Tighten the mounting screw to 2.2 Nm (20 in. lbs.).


INSTALLATION

1. Position the heater-A/C housing to the dash panel be certain that the evaporator condensate drain tube and the housing mounting studs are inserted into their correct mounting holes.
2. Install the nuts that secure the heater-A/C housing to the mounting studs on the passenger compartment side of the dash panel. Tighten the nuts to 4.5 Nm (40 in. lbs.).
3. Install and tighten the nuts onto the heater-A/C housing mounting studs on the engine compartment side of the dash panel. Tighten the nuts to 7 Nm (60 in. lbs.).
4. Unplug or remove the tape from the heater core tubes. Connect the heater hoses to the heater core tubes and fill the engine cooling system.
5. IF the vehicle is not equipped with air conditioning, go to Step 10. if the vehicle is equipped with air conditioning, unplug or remove the tape from the accumulator inlet tube and the evaporator outlet tube fittings. Connect the accumulator inlet tube coupler to the evaporator outlet tube.
6. Unplug or remove the tape from the liquid line and the evaporator inlet tube fittings. Connect the liquid line coupler to the evaporator inlet tube.
7. Evacuate the refrigerant system. Refer to: Heating and Air Conditioning, Service and Repair, Refrigerant System Evacuate, Refrigerant System Evacuate

8. Charge the refrigerant system. Refer to: Heating and Air Conditioning, Service and Repair, Refrigerant System Charge, Refrigerant System Charge

9. Reinstall the PCM to the dash panel.
10. Reinstall the instrument panel in the vehicle.Refer to: Body and Frame, Interior Trim, Dashboard/Instrument Panel, Service and Repair, Instrument Panel Assembly Replacement, Instrument Panel Assembly Replacement

11. Connect the battery negative cable.
12. Start the engine and check for proper operation of the heating and air conditioning systems.





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