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Re: Voltmeter - 1990 200TQ 10V




> 
> Voltmeter - 1990 200TQ 10V
> 
> 
> 
> 
> This problem isn't causing me any grief, however I find it rather annoying
> and have pulled the dash apart trying to fix it.  I've stabilant 22a'd every
> connector in sight to no avail, and I'm wondering if any of you have any
> suggestions.
> 
> The voltmeter moves from the far left resting position to the first mark
> indicated on the gauge when the car is running.  Only once since I've owned
> it has it read ~13 volts.  When turned off the reading drops down to the
> 'rest' position on the gauge.  The diagnostic built into the climate control
> system (does anyone know what all the codes for this are?) on item 11 shows
> ~13.4 volts consistently.
> 

A little lesson on the path of the battery cables.....

You have a cable running from the alternator to the jumpstart post
on your passenger side fender, then back towards the firewall on the
passenger side as well.  It comes through the firewall just above the 
passenger side floor, then through the passenger side sill, under the
back seat and of course connecting to the battery.

The voltage guage is showing current at the battery NOT the alternator.

The A/C voltage is coming from the fuse box, which is spliced to the
cable before the metal splice.

Metal splice you ask ?  aaahhhhhh, this is the little nasty underneath
the passenger side floor that is approx 4" long and where the cable connecting
your positive battery terminal and the jumpstart post connect together.

If ya have a multimeter, do the following:

Start it up, in neutral, with the emergency brake on... :-)

Check the voltage at the jumpstart post.  probably 13.4 or higher.

Now pull the backseat out, and check the voltage at the battery.

If the reading is less than .05 of what the jumpstart post say's you probably
have corrosion at the previuosly mentioned "Metal Splice".


I'll attach the fag (I wrote) regarding this subject...


                              "Gory Details"

                                   for

                 "Troubleshooting and Correcting the dreaded
                 12.5 at the Battery - 13.7 at the Alternator"



> The car runs great but this little glitch is driving me nuts.
> 
> On another note, a non-dealer, self-professed, Audi specialist/mechanic
> advised me that the boost gauge on the dash is a 'toy' and inaccurate.  Any
> comments?  I personally don't think there is any reason to think that the
> gauge was anything but accurate. Doesn't it get it's info from the engine
> management computer?
> 

This is true.

Some of the listers who have turbo cars can attest to this.  I own a V8, no turbo..


> BTW - has anyone had the final say on maximum wheel/tire fitment for this
> model?  It has the flat top arches over the rear wheels - I don't mind
> rolling the fenders inside but I don't want to mess with the lines outside.
> Would also like to lower the ride height by one to two inches anyone BTDT?
>

There are plenty of btdt listers here, I'm sure one of them will respond :-)

 
> OMBTW - Just finished watching 'Ronin' - outstanding!! Does anyone know who
> drove and/or who prepped the car and what was done to it?
>

I saw it this week at the hotel I was at.  Way cool watching that S8 scream
around france!
 
 
Regards,

Mike L.
90 V8 (Mine)
91 V8 (Hers)


    _/_/_/  _/    _/  _/     _/      Mike LaRosa
   _/      _/    _/  _/_/   _/       TSE - HAS
  _/_/_/  _/    _/  _/  _/ _/        2 Omni Way
     _/  _/    _/  _/   _/_/         Chelmsford, MA 01824
_/_/_/   _/_/_/   _/     _/          			 				     		 
E N T E R P R I S E		     Phone:	978/442-1250
  S E R V I C E S		     Fax:       978/442-1418
				     Email:	mlarosa@east.sun.com
======================================================================




                              "Gory Details"

                                   for

                 "Troubleshooting and Correcting the dreaded
                 12.5 at the Battery - 13.7 at the Alternator"
 
Some Potential Symptoms:

A) Car starts and runs fine,  The dash gage measures a little low, but
   there aren't any numbers on the voltage gage, so you don't really
   notice it's been slowly sitting more and more to the left.....

B) Every time you run the A/C for an extended time the car won't turn
   over the next time you stop and try to start it again.......

C) Battery dies for no apparent reason, you jump start it and leave all
   electricals off, because you wan't the battery to charge back up...
   you go to your friendly mechanic... and what does he/she do ? pops the
   hood (Not the back seat) and measures the voltage at the jump start post
   (Which is a direct connect to the alternator) and low and behold the
   output is 13.7.....  they announce looks ok to me, maybe you need a new
   battery ? ) $50.- to $100.- bucks (New Battery) and a week later, it
   does it again!!! Doooooohhhhhhhhh!!!!


Ok,  The reason the A/C kills the battery in this instance is when you
turn on the A/C it turns the electric radiator fan onto hurricane mode
and it sucks huge amounts of juice from the battery.  As it is when 
the electrical system is working properly it barely keeps up to the 
current draw. With the battery barely getting any charge from the alternator
the battery dies fairly quickly.


Next Ok,  Why does the jump start post measure 13.7 and the battery 12.5 ?
because the wiring harness for the charging system goes like so:

Alternator LUG--Cable-- Jump start Post
            |
            |
            C
            a
            b
            l
            e
            |
            |
         Firewall
            |
            |
***    Pressed Clamp  (Your problem area)
            |
            |
            |------- link to dash cluster gage
            |
            |
         Battery



Problem:

The "Pressed Clamp" is a metal tube about 3-4" long in which the battery
cable is inserted into one end and the alternator cable inserted into
the other.  Then's it's pressed together to form a connection.

Inside the clamp it get's corroded with the green goo just like your
battery post's used to when you owned cars where the battery was under
the hood :-)


Vehicles that can be affected: 5000/100/200 (likely the V8 as well...)


Tools Needed:


              Multimeter w/point attachment (Digital preferred)
              Wrench to disconnect battery
              Seriously heavy duty wire cutters to cut battery cable
              Wire Brush
              (4) Chrome hose clamps - (3/8" wide) x 1.5dia" or so
                  (with hex head preffered)
              Vise Grips
              Nut Driver w/socket that fits above hose clamps
              Grease or Lithium grease in a spray can will do
              4" x 4" piece of 1/16" thick rubber - I used old motorcycle tube
              A Printout of these instructions when you start(Seriously)
                (You'll be taking notes.....)

              Sharp Carpenters Knife or New Razor Blades.....something good
              enough to cut the plastic of the battery cable.
              Plastic Electrical tape
              Cold Beer - (Optional)


Everything else but the Beer is a must, I would read the procedure
to get an understanding of what's involved and why you want all this
stuff before you start.

This way, If you don't have some of the tools, you may be able to
come up with some suitable substitutes in advance.


Troubleshooting:

Background.... I've been through this on my wife's 89 100 Avant 125k miles,
after 2 voltage regulators(1 cheapy $25.-, and a $50.- Bosch), 1 Alternator
belt, and 2 alternators... (Don't get one from PEP Boy's, mine lasted
1 day then died.) and a tremendous amount of cursing....  I decided to
devote a day to getting to the bottom of this debacle myself.



_____________________  These spots are for you to write down
                       your findings as we explore the problem.


Preliminaries:

- Take out the back seat.

- Open the hood.

- Front of car on ramps helps, but is not required. Remember to block
  tires and use emergency brake, unless of course you have bad emergency
  brake levers on your rear calipers, then DON'T grab the emergency brake,
  just block the tires :-)


1) Measure battery with the car OFF ______________ 
   Your Target is (12.8 +/- .1)

  -If it's below target, it's not being charged sufficiently or
   the battery is on the way out.  How far along is the battery
   in it's projected life span ?

   (Believe it or not I had Sears check the battery with a Bear machine
   of some sort that put a load on it, looked ok, then they charged it
   and gave me a loaner battery for a few day's... whilst mine sat around
   for a few day's to see if it discharged.  It didn't,  battery was ok)

   Keep reading...


2) Measure at Jump start post with car OFF ____________________. 
   Your Target (12.8 +/- .2)

  -If battery measures 12.8 and jump start post is at 12.5 or
   less your losing voltage from a bad connection in the
   cable somewhere.... Keep Reading...


START YOUR ENGINES!!!!, Imagine checkered flag waving... sorry, getting
off track...


3) Grab the multimeter with a pin point end.  Measure voltage at the
   jump start post with car RUNNING ___________________.
   Your Target (13.7 +/- .2)

  -If voltage fluctuates wildly, as in more than .5 volts, possible
   regulator.  $25.- (Cheap..) to $50.- (Bosch)

  -If voltage less than 13.7, I'd bring it somewhere reputable and have
   the alternator tested.  It should put out an easy 13.7, could be as
   easy as new brushes.

  -KEEP READING, you may have more problems.... let's get 'em all
   checked out while where here.


4) Measure at Battery with car RUNNING ______________.
   Your Target (13.7 +/- .2)

  -If 3) meets target, but you fail here with less than 13.5, 
   keep reading.....


SHUT THE CAR OFF.

How'd you do ?  you probably failed somewhere or you wouldn't be
doing this on a sat/sun instead of watching the ball game with
a frosty beer in hand... :-)


OK,  If you failed and got the dreaded 13.7 Alt - 12.5 Bat, again...
Keep Reading.....


The Fun Part...


Follow the Positive cable from the alternator, it travels across
the top of the passenger side frame rail into the firewall at the
passenger side foot well.

Pull up the carpet on the passenger foot well.

On the top of the foot well on the right side, you'll see the
cable coming through.

Start up the car and poke that positive side pointy end on the
Multimeter through the cable to check the positive voltage.  Check it
before and after the "Pressed Clamp".  The "Pressed Clamp" Looks like
a 3 - 4" long by maybe .5" thick shrink wrap section on the cable.

On the wife's car it measured 13.7 on the alternator side and 12.5
on the battery side.....


If this is what you get, go grab a frosty out of the fridge, you've
just figured out the problem :-)

=====================================================================

Whilst drinking said Beer,  you get to decide do I go out and buy a
new cable from Audi for $430.- bucks or do we fix this puppy
right know with all the Tools/Supplies outlined above ?

I vote we get it over with and continue.


- First things first,  DISCONNECT THE BATTERY!!!!!!!!!!!

- Back to the passenger footwell...  pull on the cable and see if
  there is any slack.

- Your gonna need about 3-4 inches.

- If NOT, there is a clamp near the alternator where the cable is
  bolted in.  Unbolt it from there and you'll get the slack.


Back in the car at the passenger foot well....


- Once you have the slack, get the Big wire cutters and cut out the
  Dreaded "Pressed Clamp".  Making sure to cut as close to the clamp
  as you can.

- Strip approx 2" of insulation from both sides.

- Put the 2 Chrome clamps on each cable loosely.

- Put the 2 cables side by side so that the bare ends both touch
  each other's plastic sheathing.  I'd try to make an ASCII drawing
  but the picture would be more confusing than helpful......


Feel free to give me a buzz and I'll fax a drawing.....

978-442-1250 Work Number.....


- Here is where we'll need the Nut Driver and the Vise Grips,  Line up the
  Chrome clamps on the exposed cable a 1/4 inch or so from the ends.
  So that there is a 1/4 inch of cable showing between the clamp and
  the plastic sheathing.  Hopefully this makes sense...

- Use the Vise Grip to hold the clamp in place, this will also give you
  some leverage when your tightening it with the Nut Driver.

- When it's tight.  Put the Rubber section over the area and loosely clamp
  it on.


  Here's where we get to start the car up and re-measure with the
  multimeter :-)  Just make sure the cable is not exposed anywhere!!!

  Don't forget to hook up the battery.....

  I'm going to assume success......


- Ok, NOW DISCONNECT THE BATTERY!

- Take the rubber off the cable.

- I put a piece of cardboard behind the working area of the cable and
  sprayed it heavily with Lithium Grease.  It's all I had at the time.

- I think a good heavy hand applied grease might work better here, glop
  it on thick.  This will hopefully slow down the corrosion enough that
  next time it happens, you won't own the car :-)


  Where in the home stretch......


- Put the rubber section back over the cable and make sure it's big
  enough to cover the whole thing and then some.  Secure it with the
  other 2 cable clamps.

- Wrap nice and tight and completely with Plastic Electrical tape,  This
  will help keep out any moisture as well as keep it all in a nice bundle :-)


RECONNECT BATTERY AND TRY IT AGAIN.

- Wouldn't want to put everything back together and find we missed
  something.

- Everything working ok ? Yes, Excellent, put it all back together,
  sit back have a couple more beers!!!



Hopefully my anguish over this will help somebody else save some time, money
and frustration.  I know other people on the list over the years have
saved me lot's of both :-)