why does the inside fan run when even turned off?
Hello, 2 things... I don't remember if Centuries had climate control or not... If so, then fan module located at firewall next to fan in the plenum, but under a shield all the way across firewall is bad; ie, will allow power to fan when switch if off...Very common on all GM's with Climate Control. If no auto air, remove large wire from alternator, and see if fan goes off, if so, you have an open in the diode trio of the regulator within the alternator. Hope this Helps, AskTrannyMan
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