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Q: AC works but only blows warmest or coolest

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AC works but only blows coldest or warmest. If you start the car with the coolest on it blows cold (coldest it can be) and if you turn the button it stays the same until you reach the middle (or red line) - then it swap and blows out the warmest. And then it it doesn't change back to cold (it has done intermittently if I turn air off, turn to coldest, turn air on)

So the issue is that I cannot change temp when driving and it's earthed coldest or hottest.

It wasn't always like this, it just happened on day and has been like that for the last 6 months

Thanks for all help

My car has 130000 miles.
My car has an automatic transmission.

Hello, thanks for writing in. This is almost always caused by a bad blend door motor on this vehicle. I have rarely seen anything else fail on this vehicle that causes the same issue. It can be the module, but that is not common at all. The blend door motor fails under the dash and causes this. I usually test if first and make sure that the blend door is moving correctly and if it is then I replace the motor. If you want to have this AC problem checked, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose and repair this.

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