[200q20v] 200q20v] diff lock from hell possible fix

[Brian Link]

Light on = differential is locked.  My friends lock would do the same thing
as you describe.  The fix was to clean all the soda, coffee and crumbs out
of the switch.   Remove it, open it up, clean it with IPA, or rubbing
alcohol, re-install.   This is assuming that the vacuum system to the diff
lock is in good shape.

Brian Link

Date: Wed, 23 Jan 2002 20:35:51 -0500 (EST)
From: Chris Covington <malth at umich.edu>
To: <200q20v at audifans.com>
Cc: <quattro at audifans.com>
Subject: [200q20v] diff lock from hell

<Snip>

So today I get in the car, fire it up, and I see the Anti-lock off light
again, then the green diff lock light in the diff diagram, hmm.. it seems
that the diff lock has engaged again.  I was able to turn it off (ABS
was re-enabled, the green light was off) and get where I was going with
the diff unlocked.  I think it was physically unlocked too, the car
didn't feel squirrely or scrub the tires around corners.  So on the way
home I fire up the 200q20v again and what do you know, it's engaged and
I can't disengage it.  I tried shutting the car off, back on, and
immediately disengaging it but this didn't work, so it seems I'm
perma-difflocked now.

Has this happened to anyone before?  Also, when that yellow
crescent-shaped light is illuminated on the diff switch, is the diff
supposed to be on or off?

Chris
'91 200q20v