I have an 89 98 with an A/C problem. The A/C has started blowing hot air sometimes, not all the time just most of the time. It worked great up till 2 months ago. It has plenty of refrigerant and no leaks. I can set the control thermostat on 60 and the blower will kick in blowing hot air. The mechanic I used to check the refrigerant messed with it some but was unable to figure it out. I'm leaning towards an electrical issue but I have no schematic or guidance at this point. Any help would be greatly appreciated.