GM 91171580
Evaporator Core

The first step requires refrigerant removal for recovery before disabling the supplemental inflatable restraint (SIR) system. The worker should then disconnect the negative Battery Cable. The first step requires the removal of the blower case and subsequent disconnection of power from the a/c compressor control module and the refrigerant temperature sensor. The next step requires removal of Evaporator case pipes that link to both the refrigerant inlet and outlet as well as separation of the drain hose. Two mounting bolts and one nut along with the Evaporator case need to be removed first. Unhook the two lower releases securing the a/c compressor control module before pulling it upward to break its attachment with the Evaporator case. After releasing the retaining clips workers should separate the two Evaporator case (1,3) halves before removing the core. The new Evaporator core must go inside the Evaporator case before securing the upper half and lower half through retaining clips while reinserting the a/c compressor control module. Hook the Evaporator case into position on the vehicle by using both mounting bolts and the nut for attachment. First reconnect the drain hose with the refrigerant inlet and outlet pipes to the Evaporator case then connect the electrical connectors to the a/c compressor control module and the a/c Evaporator temperature sensor. Reinstallation of the blower case is necessary after enabling sir and reinstalling the negative Battery Cable and performing an evacuation and recharge of the a/c system before checking for refrigerant leaks.