Loss of Fan control from Climate Control, 87 5kcstq

[Orin Eman]

> 
> The subject line pretty much tells all. My climate control blower fan is
> doing the opposite of the usual failure (the fan is only ~3 years old
> and runs fine) in that as of yesterday it started running at full speed
> regardless of the CC setting (yes, it even ran full blast on the "off"
> position). The problem is intermittentent (aren't all Audi electrical
> issues?). The opposite problem/cure seems simple, change the blower
> fan...this no doubt gets more involved. I know there is a speed control
> box someplace and will sit with book-o-Bentley and properly troubleshoot
> this when I have time and will report the fix to the list...I was just
> hoping there could be a BTDT shortcut I could follow.

Climate control is haunted.  Perform exorcism.

(My 5k is doing the same thing...)

The speed control power electronics sit on top of the
evaporator.  I'm thinking bad connection, bad ground
or the power stuff is toast.  You should be able to
check the control signal at this point - see if it makes
sense.  Someday soon, I'll get around to looking at mine.

Orin.