Q: AC/heater fan runs constantly even with switch off

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Lost fan speed control and fan keeps blowing even with the switch off. AC still works but AC fan keeps blowing

My car has 138000 miles.
My car has an automatic transmission.

The most common cause of this problem is the blower motor control processor mounted in the A/C evaporator case. I’d start by checking that first I were you. I you need some assistance however, feel free to contact a professional mechanic who can diagnose your A/C system firsthand and make the necessary repairs.

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