GM 19213200
A/C Hoses

The repair process for trailblazer ext and envoy xl hvac hose/line requires professionals to first recover refrigerant from the system using the halogen leak detector (J 39400-A). The halogen leak detector (J 39400-A) should be used to verify leakproof conditions in all component fittings. Release the compressor suction/discharge hose nut at the compressor's port as well as the compressor suction/discharge hose while uninstalling its sealing washers. You must detach the compressor suction hose nut from the accumulator while you disconnect the hose and o-ring seal from its position on the accumulator. Start by removing the bolt from the lift bracket and nut from the engine stud before removing the compressor discharge hose from the condenser and the nut from the compressor hose connection in the driver wheel opening. O-ring seals should be removed before plugging or capping all open connections. New o-ring seals need installation before connecting and tightening the compressor discharge hose to the condenser at a torque of 28 n.m (21 lb ft). Place the compressor hose on the driver wheel opening connector and torque its nut to 48 n.m (35 lb ft). First thread the compressor suction hose to the engine stud where you should tighten the nut to 48 n.m (35 lb ft) before finally connecting it to the engine lift bracket through a bolt torque to 48 n.m (35 lb ft). The compressor suction hose connects to the accumulator before installation of the suction hose nut which must be tightened to 48 n.m (35 lb ft). Secure the retaining nut with a torque of 33 n.m (24 lb ft) after you attach the compressor suction/discharge hose and install its washers. Empty the system of air and refill the a/c system.

A refrigerant recovery process must occur before replacing the evaporator tube within trailblazer ext and envoy xl models. First disconnect the evaporator tube from both the evaporator along with the auxiliary evaporator tube from the secondary piping. The evaporator tube nuts must be removed from the condenser before you proceed with taking the evaporator tube away from the fender fixation points 1 and 2. Secondly remove both the washer solvent container along with the coolant recovery tank. You must use the orifice tube remover (J 26549-E) along with the evaporator tube to remove the component while disposing of the o-ring seal. After installing a new o-ring seal the technician should connect the evaporator tube to the evaporator while tightening the nut to 28 n.m (21 lb ft). Secure the auxiliary piping to the auxiliary evaporator tube with a nut torque at 28 n.m (21 lb ft), and proceed by connecting the evaporator tube to the condenser where a torque of 28 n.m (21 lb ft) should be applied to the nut securely. After reattaching the coolant recovery tank and washer solvent container the technician must tighten the nuts (1,2) which secure the evaporator tube to the fender at 28 n.m (21 lb ft). You must evacuate, recharge and test for leaks of the a/c system through its components by utilizing the halogen leak detector (J 39400-A).

Follow the Straight Line Repair procedure for straight sections and the Line Sectioning Repair procedure for bends, replacing lines in bend areas to maintain original shape and prevent vibrations.