Heater Core

* The vehicles in question are equipped with airbags. At any time, with the battery connected, the airbag (which has a rigid structure) may deploy (inflate). To prevent accidental airbag deployment (and possible injury) when performing any work near airbag components, turn the ignition key to the LOCK position and disconnect the battery ground cable. After disconnecting the battery, wait two minutes (required for the backup capacitor to fully discharge). For a more detailed description, see Subsection 12.24.
To remove the heater radiator, the manufacturer recommends removing the entire instrument panel and steering column. This requires disconnecting a large number of connectors, so there is a risk of breaking fragile plastic latches, retainers, etc. on various components. This method is not practical for home workshop use due to its complexity. The radiator can also be removed without removing the instrument panel. The procedures are described below.
The heater radiator removal procedure is described in detail below. It is much easier to remove the radiator after removing the evaporator; however, this requires discharging the air conditioning system and recovering the refrigerant first.
For the evaporator removal procedure, see Subsection 4.14. Before depressurizing the system, be sure to read the warning in Subsection 5.2.

Removal

PROCEDURE
1. Disconnect the battery ground cable.
2. Drain the coolant (see Subsection 2.8.4).
3. Working from the engine compartment side, disconnect the heater hoses at the engine compartment firewall (indicated by arrows). Push the rubber grommet on the firewall into the passenger compartment, disengaging the grommet flanges from the edges of the firewall opening.
4. Remove the center console, glove box, glove box trim, ashtray, radio, and center console side panels.
5. Referring to the description in Subsection 4.10, remove the heater/air conditioner control panel.
6. Referring to the description in Subsection 5.11, remove the electronic control unit without disconnecting the connectors from the unit. Move the control unit aside to provide sufficient working space under the heater radiator housing.
7. Under the instrument panel there are two gold-colored brackets attached to the body floor. Remove the mounting bolt (indicated by arrows) of the left bracket to the body floor, as well as the bolts securing the ground wire connections, but do not remove the bracket completely. Remove the mounting bolts of the right bracket and remove the bracket from the vehicle.

* On the back side of the plastic instrument panel, the bracket is secured with Phillips-head self-tapping screws threaded into the plastic. To remove them, use a Phillips screwdriver with a tip size exactly matching the screw heads. When removing the screws, press the screwdriver firmly and keep it aligned to avoid cam-out. The screws are tightly fastened, so the heads may be stripped if removed incorrectly.
8. Remove the mounting bolts and remove the center air duct channel.
9. Remove the duct section assembly with the air distribution flap, located directly above the heater radiator and slightly offset forward. This is necessary to increase the working space around the heater.
10. Loosen the nuts on the studs securing the left side of the evaporator housing (see Evaporator Removal illustration). The heater unit is secured by three studs to the engine compartment firewall. Remove the nut from the stud near the upper throttle pedal lever (indicated by arrow).
11. Remove the nut and stud at the lower right corner of the heater housing (indicated by arrow).
12. Remove the last nut at the lower right corner of the heater housing (indicated by arrow).
13. Once the mounting lugs of the heater housing have slipped off the studs and the edge of the air conditioner evaporator housing is clear, remove the heater assembly from under the instrument panel by lowering it downward. Spread a large amount of rags on the floor mat to absorb any spilled coolant.

* Work slowly and carefully to avoid damaging plastic components when removing the heater. The heater assembly can be removed as follows: first pull the heater away from the engine compartment wall so that the lugs disengage from the mounting studs, then shift the heater to the left to clear the evaporator housing, lower it down, and remove it from the vehicle.

14. After removing the heater from the vehicle, remove the two screws and the clamps securing the heater tubes (indicated by arrows) to the housing.
15. Remove the heater radiator from the housing.

Installation

PROCEDURE
1. Installation is performed in the reverse order of removal.

* Due to assembly line design considerations, the nuts securing the heater housing and evaporator to the engine compartment firewall are designed for single use. Therefore, new metric-thread nuts and spring washers must be obtained before assembly.

2. Fill the cooling system with fluid, start the engine, and check for leaks and heater operation.