GM 89019173
Heater Core

The first thing to do when changing the Heater Core is to drain the coolant. Take out the storage compartment from the instrument panel, cut off the necessary wires and get rid of the center floor air duct. After that, take out the hinge pillar trim panels, blower motor cover, blower motor and Steering Column. Pull out the instrument panel and take out the coolant tank and the heater hoses that are connected to it. Grip the heater case as you remove the single screw on the cowl's interior and after that, unfasten the 4 screws and 2 nuts inside the cowl that are found on the engine side. Lift off the heater case and ask someone to help you if the piece is heavy. After that, unscrew the 7 bolts securing the heater cover to the heater body and take off the heater cover to take out the Heater Core from the bracket. Put the new Heater Core into the retainer, attaching it with the 7 screws. Before installing the heater cover, make sure to put in new seals and ensure that cover is sealed tightly. Install the heater case and feel free to ask for help if it's difficult; after it's in place use the supplied nuts and screws to fix it on the engine side and the coil side, tightening the screws to 1.9 n.m (17 lb in), the nuts to 2.8 n.m (25 lb in) and the inside cowl screw to 11 n.m (97 lb in). Reconnect the heater hoses, set the coolant recovery reservoir, pull the instrument panel backward and put back the Steering Column, blower motor, blower motor cover, hinge pillar trim panels, center floor air distribution duct and electrical connectors. Don't forget to install the storage compartment in the instrument panel, add engine coolant and check that there are no leaks in the system.

The first step to replace the Heater Core includes draining the coolant. The instrument panel storage compartment must be removed first followed by the necessary electrical connector disconnections and center floor air distribution duct extraction. Begin the procedure by pulling off the hinge pillar trim panels before removing the Blower Motor cover and motor unit together with the Steering Column. You should begin by removing the coolant recovery reservoir and heater hoses at the instrument panel before rolling back this panel. The screw at the evaporator pipe interior should be removed first when the heater case is held against the cowl followed by the 4 screws and 2 nuts securing the heater case to the cowl at the engine side before removing the heater case. If needed, ask for assistance. Extract the Heater Core by pulling it out of the retainer after removing 7 screws that protect the heater cover and taking off this cover from the heater case. Installation of the new Heater Core includes inserting it into the retainer which must be tightened with seven screws while replacing its seals before reinstalling the heater cover and checking the proper seal. Reinstall the heater case with assistance if required and fasten it using nuts and screws from the engine side of cowl according to 1.9 n.m (17 lb in), 2.8 n.m (25 lb in) and 11 n.m (97 lb in). The technician should first reconnect the heater hoses and coolant recovery reservoir and then roll forward the instrument panel before reinstalling the Steering Column, blower motor, blower motor cover, hinge pillar trim panels, center floor air distribution duct and reattaching all electrical connectors. After installing the instrument panel storage compartment it is necessary to add engine coolant while also conducting a leak inspection on the system.

Start the replacement process of the heater core in the auxiliary HVAC module by first recovering refrigerant from A/C systems and draining engine coolant. Disconnect the heater lines (2, 3) and air conditioning lines (2, 3) which originate from the auxiliary HVAC module present underneath the vehicle. First remove safety stands from the studs that hold the auxiliary HVAC module before lowering the vehicle. To proceed with installation begin by taking off the right rear quarter trim panel and unplug electrical connectors from the Real Time Damping (RTD) Module when required. Pull the upper auxiliary air duct fastener then raise the duct into the headliner area. Move the fasteners from the rear auxiliary HVAC module retention sites before you extract it to a work station. The first step is to detach the air temperature actuator then the heater core cover and finally the heater core from the module. The module gets the new heater core while the installation requires heater core cover and air temperature actuator placement afterward. After insertion of the auxiliary HVAC module assembly back into the vehicle space through two installed bolts. Connect the upper auxiliary air duct to the air distributor duct by using fastener and reestablish the electrical connections. The installation requires adding the RTD Module followed by reinstalling the right rear quarter trim panel. After another vehicle lift the auxiliary HVAC module demands two nuts secured at 9 N.m which is equivalent to 80 lb in. Fasten air conditioning lines (2, 3) and nut to the auxiliary HVAC module before tightening the nut to 16 N.m (12 lb ft) while also connecting heater lines (2, 3). Perform the following steps: Remove the safety stands, slowly lower the vehicle after which you need to add new engine coolant then charge the air conditioning system with refrigerant.

The service process for a heater core begins by draining engine coolant first while recovering refrigerant. You must begin by taking out the heater/vent module followed by unfastening the heater core cover screws before extracting the heater core cover in order to reach the heater core. Place the replacement heater core before installing the heater core cover and attach screws according to the manufacturer recommendations of 1.6 N.m (14 lb in). Reinstall the heater/vent module and then complete coolant system refilling before recharge of the air conditioning system.

The first step to replace the Heater Core includes draining the coolant. The instrument panel storage compartment must be removed first followed by the necessary electrical connector disconnections and center floor air distribution duct extraction. Begin the procedure by pulling off the hinge pillar trim panels before removing the Blower Motor cover and motor unit together with the Steering Column. You should begin by removing the coolant recovery reservoir and heater hoses at the instrument panel before rolling back this panel. The screw at the evaporator pipe interior should be removed first when the heater case is held against the cowl followed by the 4 screws and 2 nuts securing the heater case to the cowl at the engine side before removing the heater case. If needed, ask for assistance. Extract the Heater Core by pulling it out of the retainer after removing 7 screws that protect the heater cover and taking off this cover from the heater case. Installation of the new Heater Core includes inserting it into the retainer which must be tightened with seven screws while replacing its seals before reinstalling the heater cover and checking the proper seal. Reinstall the heater case with assistance if required and fasten it using nuts and screws from the engine side of cowl according to 1.9 n.m (17 lb in), 2.8 n.m (25 lb in) and 11 n.m (97 lb in). The technician should first reconnect the heater hoses and coolant recovery reservoir and then roll forward the instrument panel before reinstalling the Steering Column, Blower Motor, Blower Motor cover, hinge pillar trim panels, center floor air distribution duct and reattaching all electrical connectors. After installing the instrument panel storage compartment it is necessary to add engine coolant while also conducting a leak inspection on the system.