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Q: I just changed the battery and alternator. Now my air conditioner is blowing hot. What can I do?

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I just finished changing my battery and my alternator and now my air conditioner is blowing hot air I do not know why it is but I would like to find out what I can do to fix it

My car has 50000 miles.
My car has an automatic transmission.

A: Hello. If you recently serviced the electri...

Hello. If you recently serviced the electrical system and now your AC is no longer working then it may be possible that the issue is related to the work. The first thing I would do is check the vehicle’s fuses and relays. It may be possible that one of the fuses or relays blew when the battery or alternator were disconnected. This does not always necessarily indicate a major issue, but can be the result of one if a fuse continues to burn out repeatedly. If one of the fuses related to the the AC system has burned out it can cause the system to malfunction. I would also check the vehicle’s interior fuse box, as there may be fuses related to the AC located there as well. If the fuses and relays are all good then it may be possible that there is an issue with the AC system. Hot air can be caused by many things, ranging from low refrigerant in the system, to a faulty sensor or switch. A proper diagnosis of your air conditioning system by a professional technician would be required to determine what the exact cause may be.

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