AC out defrost vent only on HIGH.

[Alex Kowalski]

Ron wrote:

>So anyone want top stop me & tell me otherwise??
>Thanx

The only thing that I remember is that the climate control defaults to the
"defrost" setting when there is a system fault, which *should* be registered
by the head unit.  Have you checked the codes on the existing AC head unit
and watched the graphic as this weird behavior happens?  It sounds like the
head unit is flaky, but it would be nice to see if it's reporting any codes
before you replace it.  I can help with that if you email off-list.

Cheers,
Alex Kowalski
'87 5KCSTQ
'86 5KCSTQ