HVAC heat issue?

2009 BMW 335
109,000 MILES • 6 CYL • TURBO • 2WD • AUTOMATIC
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BHAMDOC1973
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My son's car. It has gotten super cold here and it may be a coincidence, not sure. But the heat would just cut off while driving everything stops then comes back. But the main problem is that when you turn the speed dial too high it does not blow full power, so he can hear the blower change speed but the amount of air out of the vents is the same. Blower speed changes fine. Found this code.
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Jan 21, 2024 at 3:03 PM
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STRAILER
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Okay, I would try replacing the sensor and then clear the codes. Also, when the heater stops working are both heater hoses going into the firewall hot. Make sure to check the coolant level. Please go over this guide and I have included the sensor location in the images below:

https://www.2carpros.com/articles/car-heater-not-working

It could be the air mix door is not working as well. Here is the location for that so you can check it out as well. Check out the images (below). Please let us know what happens.

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Jan 22, 2024 at 11:43 AM
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BHAMDOC1973
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so, the sensor is behind the vents? the heat now comes out from the vents, son didn't pay attention to the button pressed to defrost.
Jan 22, 2024 at 12:14 PM
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STRAILER
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It looks like the sensor is behind the glove box, so the heat works now?
Jan 23, 2024 at 10:11 AM
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BHAMDOC1973
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Yes, the heat works and comes out of the vents. Son not focused enough to realize the button was lit on feet and not vents, lol.
Jan 23, 2024 at 10:17 AM
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STRAILER
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I happens, glad you got it fixed.
Jan 24, 2024 at 9:39 AM