Ok so about 8 months ago before I actually got this car the battery was unhooked for an unknown period of time. And ever since the car has had issues with heating and cooling. If it's cold outside both my AC/Heat blows cold. And when it's hot outside both blow hot air. The thermostat was replaced maybe 3 months ago and that didn't fix the problem. My mechanic told me it would cost 300 dollars just for them to look into the issue. Does anyone have any answers that can help me out before I fork over that kind of cash. Thanks!I was wondering if maybe the battery being out for a prolonged period of time could throw off my climate control.
The heating unit on most GMC/Chevy blazers are controlled by the engine's vacuum. If the HVAC line on the engine (usually on the top of the engine in the rear) is disconnected then it won't change the climate controls.
I seriously doubt that your HVAC problems are related to the disconnected battery, but then if seen stranger things happen with vehicles... More likely you have a problem with the vent system as the other person has indicated. When you want cold air, if the vent system is malfunctioning, the air is not being completely vented through the evaporator. When you want warm air, the air is not being completely vented through the heat exchanger. I would check the vacuum lines, as previously indicated. In addition I would take a look under the dash and see if the linkage wires are stuck.. if they were not used for a period of time perhaps they need to be exercised by hand and/or have some lubricant applied. Be gentle, though, so you don't bend or break anything. Do you have a repair manual for your specific vehicle? If not, it would be a good investment, even if you resort to the less expensive Haynes or Chilton varieties available online or at your local auto parts store. I hope you get that fixed before Winter arrives, my friend. Take care, Rick
