[s-cars] heated seats

[Wayne Dohnal]

Christian,

First, congratulations on your new S-car.  It's a great car, but owning it
does have its price.  It demands frequent attention and a steady diet of
parts.  If you don't do the work yourself you have to be prepared to spend a
lot of money on it.  Don't get me wrong, I 'love' my S4, but you can't
neglect it and expect it to keep going like a typical Japanese car does.

It's very common for a newly-purchased S4 ro have an inoperative drivers
seat heater.  Many of us have done the repair.  I believe that it's the most
common for the bottom element to go out.  Mine blew the backrest element.
This is one of the more undesirable maintenance jobs.  I ended up losing a
little blood with cut up hands.  But I've been enjoying that warm seat for a
few years now and I'll fix it again if it dies again.  You will find some
writeups that tell you how to repair the burned out element.  I did that,
and after a few minutes of operation it burned out again a few inches away
from the repair.  So I got to do the job twice, with a new element the 2nd
time.  It's of course your call on the potential of saving money vs. the
risk of doing it over.  Do you have a Bentley?  It gives some information
for the job.  One thing is that you do not remove the old element, you cut
the bottom off of it and glue the new one on top of it.  And I think that
the new element is self-stick (I hope my memory is correct here).  They
don't tell you that in the Bentley.

The two elements are in series.  Assuming yours is the same as mine, here's
info for the under seat connector.  Pins 2 (blk/wht) and 4 (brn/yel) are for
the temp sensor, which I believe is in the bottom element.  Pins 1 and 5 are
for the cushion, and pins 3 and 6 are for the backrest.  In the harness
connector, pin 3 (backrest) is grounded, pin 1 (cushion) is the power feed
from the seat heater controller, and pins 5 and 6 are bridged to create the
series connection.  You can disconnect the connector and ohm the elements.
I think they're something like 1.2 ohms, but my memory is fuzzy.  Or you can
leave it connected and check the voltage at the pin 5-6 jumper.  If it's
zero the cushion is open, if it's +12 the backrest is open, and if it's +6
everything should be OK.  But this assumes that the controller is OK, so
it's best to do the ohm-ing.

This is a dealer-only part but you shouldn't need to pay list price.  I got
mine from Clair Audi on the east coast.  Sunset Audi advertises a parts
discount but I don't have any experience with them because it doesn't work
for Oregon residents, of which I am one.  You can also contact SJM Auto
Technik (info on www.sjmauto.com) and see what Scott can do for you.  If you
mail order, I suggest you have somebody on the list verify the part number
for you as the dealers seem to frequently get it wrong.

You will almost assuredly find other broken things in your new car.
Fortunately, the cars are pretty consistent and you will be able to get BTDT
advice for just about anything.  Just ask.  Common examples are the gas
pedal pad falling off, and burned out lights all over the place.  You
probably have a few burned out lights where you don't even realize that
lights exist.

Wayne Dohnal
1994 S4