Q: Heating blows cold - 2006 Porsche Cayenne

asked by on September 20, 2016

I have a problem with the heating in my car. It is blowing cold air only. This happens even though I set the thermostat on high. I had it checked and it works correctly. About a year ago, I had the coolant pipe system replaced. I also checked the coolant and it's at a good level. I was suggested to have a new thermostat installed. I did that but the issue persists. What should I do?

Heater Blower Motor Resistor Replacement $106.80 - $693.71 Get a Quote

Hello. Based on what you have described, I am almost 100% certain you need to replace your blower motor control module / resistor. Not getting AC is much more common than not getting heat because heat comes from the hot coolant running through the engine. Finding heat is easy. Making the AC blow cold is much more complicated. No heat and no other coolant related issues make it almost certain that it is the resistor that has blown for the blower.

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