Why no heat in my 2007 passat fan isn't blowing?
Check for a bad fuse, or fan relay.
Could be a number of things really. Most likely is a fuse. If all the fuses are fine, it pretty much isolates it to the system itself, which has switches, relays, resistors, and motors. All of which could be bad. You're going to have to isolate the problem. Does AC only work? Does it work only on floor heat or only on dash heat? Check every switch position possible and see which, if any come on. From there you're gonna need a voltmeter and patience.....or you could just start changing parts until it works, less technical but more expensive.
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