Discharge and recover the air conditioning system to an air conditioning technician. Take the cable that connects the battery and remove it from the negative terminal. undefined undefined Also, it is recommended to take off the upper intake manifold in order to have access to the heater hoses at the firewall. Remove the expansion valve from the evaporator core by unbolting it at the firewall. Remove the heater hoses from the heater core pipes at the fire wall. Release the pressure on the clamps and pull down the clamps again over the hoses, remove heater hoses from the heater core tubes at the firewall. Unfasten and pull the heater and air conditioning housing out of its position relative to the firewall. Summarily, touch the fasteners of the heater core tube cover. The heater core cover fasteners can now be disconnected and the cover itself can be taken off. Remove the heater core from the heater/air conditioning unit compartment. Removal is the vice versa of installation. Install new seals for the heater core fittings and replace the cooling system fluid. Transport the system to the shop that depressurised it and should have it evacuate/recharge/leak tested. Pull out the rear heater/air conditioning housing by loosening the bolts securing it to the car and place it on a bench. Loosen and take off the nut that joins the heater core tube bracket to the housing. With a slow and steady manner, slide out the two plastic retainers, while at the same time removing the heater core from the heater/air conditioning housing. To access the heater core from the housing, you need to eliminate it. Installation is the exact opposite of what is done when removing the device. Prerig the heater core and connect the hoses in a hurry. After completing the reassembly check the level of the cooling system. If the heater core was replaced and not pre-filled, thermal cycle the vehicle twice. This procedure also confirms that the heater core is full to support the functioning of the heater system. In order to apply thermal cycling to a vehicle, the car must be driven until the
Thermostat opens and then switched off and let to cool. This process requires the coolant level in the reservoir to be monitored. To verify that the rear unit is filled completely, follow this procedure: Let the testing begin with the vehicle at this set temperature. Switch on the car and let the engine warm up to reach its normal working temperature. Switch front to HI setting on the front A/C control, then turn the front system off immediately. Engage the engine, and set the rear A/C system blower to HIGH with the temperature set to HEAT. The discharge air temperature, measured by the dual register head located on the C pillar base area, should range between 55 to 65 °C.