91 200q ABS /electrical

[quk@sievers.com (Phil Payne)]

In message <32D52714.3901@earthlink.net> Sargent Schutt writes:

>>> Third Prob (and possibly related to the first): The 'worn pad' indicato> r
>>> light is always on, though the pads are not worn, and the sensors on th> e
>>> pads are fine. A break in the wire somewhere? Related to #2?
 
>> Depending on the car, that light might mean more than just worn pads. 

> According to the manual, it only means worn pads.

Yeah.  According to the manual honey bees can't fly.  The pad light circuit is 
easy to jumper out - if you do that, and the light stays on, then there's 
something else in the circuit.  Check the wiring on _your_ vehicle.  My 
original German documentation for the ur-quattro is full of handwritten 
comments like "not on serial number nnnnn".

>>> The warning/indicator screen goes psychadelic after driving for 15-30
>>> minutes.
 
>> Check chassis grounds on the sidewall under the fusebox, in the engine
>> bay and any brown wires attached to the engine.  Some of the instruments
>> have dedicated ground circuits and bad ones confuse the display.

> This I will also try this weekend. Hopefully, but others say its
> doubtful. Evidently these display systems are not reliable forever.

The recommendation is a tradeoff of effort against likelihood.  The most 
_likely_ cause is a crack in the printed circuit, but they can be _swines_ to 
find.  Bad chassis ground is less likely, but much easier to check and the 
potential for saving $$$ workshop hours is quite good.

--
 Phil Payne
 phil@sievers.com
 Committee Member, UK Audi [ur-]quattro Owners Club