The air/heat/defrost wont shut off
All the sudden the air,the heat and defrost wont shut off, they all work but on high and I press the off button and it wont turn off
Try removing the heat and A/C fuses for a few minutes then put them back in and give it a try, I have had a few control modules do this and worked fine after the reset, if it doesn't fix it then deeper diagnostics are needed, take it to a shop you trust, HVAC systems can get expensive really quick, so you don't want just anyone testing it, but someone that knows your system. HTH.
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