Q: Why is my car blowing hot air and cold air at the same time?

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The other day i took out my HVAC system from the car trying to fix the LED screen, which I did not fix. After I but the system back into the car and took it for a drive the air started blowing hot and cold. It would blow hot air from the side vents towards the doors and the floor vents. It would also blow very cold from the center vents.

My car has 66000 miles.
My car has an automatic transmission.

The answer to this depends on whether you have switched on heating, cooling (A/C) or neither. In one scenario, for example, if you have not switched on the A/C system, but the A/C is running as confirmed by a visual check of the A/C compressor, and you are getting cool air obviously there is an electrical problem. The coincidental heating could be due to a blend door malfunction. If the only thing you did was remove electrical or electronic components, it would appear that you have an electrical malfunction in the controls. I recommend you request an HVAC diagnostic and the responding certified mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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