One or more heater & AC (HVAC) air delivery and/or temperature mode door actuator may fail. This can result in incorrect air delivery or temperature. If this occurs, fault code(s) stored in the HVAC control module should be available to assist with diagnoses.Google+
Car Problem Reports
Chevrolet Suburban 1500 Heating and AC Temperature and Air Delivery Mode Door Actuators May Fail
Chevrolet Suburban 1500 Problem
part numbers to fix the ac issues are 15306189 15-72275 16192099 pt1346 if you only replace the hvac blower switch then make sure to replace to pigtail connector as well. Most common problem is these two pieces wear out and melt. Causing a malfunction. If you need to replace the whole hvac control board then get part #15-72547. You can find it online from 99-275. The dealer has it for about 275. It is really easy to replace. Just pop off the front panel. Make sure to put your emergency break on and put your key in the ignition to put your truck i. The lowest gear. The panel should come off. The hvac control panel is held on with clamps. Just pop the sides out with a small hand held screw driver. Just disconnect the old and connect the new one. It should work with no problem. On a side note. It is best to disconnect the negative terminal on the battery and make sure when you are pulling the panels you look for wiring. Oh and make sure you new hvac panel has light bulbs.
Visitor, 1996 Chevrolet Suburban 1500, 197,000 mi
heater/ac actuator door malfunction, keeps erratically opening and closing