coolant afterrun pump diagnosis

[Dave Eaton]

2 tests you can do.  remove the connections from the thermo switch and short
them.  fan and coolant pump should run. if they don't you have a wiring
issue, a fuse issue, or a fan/pump issue.

2nd check is of the thermo switch itself.  when the engine is cold, this
should be "open", and it "closes" when temp is over 105 c.

i am puzzled by the manual stating that the pump *will run* after 5 minutes.
it seems to me the heat build up in the area of the head will vary depending
on a lot of variables.  for instance, with the ur-q, i have just replaced
the pump, but it is so cold outside, and with the re-core of the alt
radiator, i cannot get the after-run system to cut-in, although it checks
out ok.

and you should thank you lucky stars that you're not trying to do these
tests on a rs2 or ur-q.  there you need your arm broken in 4 places to get
access to the necessary bits.

hth,
dave
'95 rs2
'90 ur-q

-----Original Message-----
Reply-To: <lee at wheelman.com>
From: "Lee M. Levitt" <lee at wheelman.com>
To: "Qlist" <quattro at audifans.com>
Date: Thu, 14 Jun 2001 07:01:52 -0400

Car in question is a 1995.5 S6 avant.

I've heard my coolant afterrun pump run exactly once now...immediately after
I replaced it. My mechanic had indicated that the fuse was blown for the
pump and that when he replaced the fuse, the pump sounded like it hadn't run
in a *long* time.

So I replaced the pump. No big deal. Take the car out for a quick spin, park
it. Pump and fan both go on as expected. Shut off as expected.

That was 5 days ago. I haven't heard the pump run since. It *should* have
run, given the heat, etc. Wazzup?

I've checked the fuse (I *think* it's the correct one)...passenger side kick
panel, first fuse in box (there's only two, and both seem fine).

I don't know what else to do/check...

Thoughts?