Voltage drop reading on guage '83 Coupe

[Ben Swann]

Huw,

I knew you would know.

The car was reported to have "cut out" when run recently after sitting for
awhile and a lot of electrical devices being used at the time, and would not
restart.  Car was towed to gas station where after fill-up with high test
and dry gas, was restarted.   No problems since.

Owner thought this volatage reading had something to do with it.  I think it
was likely he had some water in the gas.  Car has not required periodic
jumping of battery charging.

The only way I could see to improve the voltage reading on the guage to
match the battery voltage is to run a separate circuit to the guage with
separate return to ground.  I recommended DFIIAB approach, and as far as I
can tell nothing is really broken.

Ben
----- Original Message ----- 
From: "Huw Powell" <audi at humanspeakers.com>
To: "Ben Swann" <benswann at comcast.net>
Cc: <quattro at audifans.com>
Sent: Thursday, February 05, 2004 2:09 PM
Subject: Re: Voltage drop reading on guage '83 Coupe


>
> > Is it normal for the voltage reading on guage to read about 1-2V
> > lower than battery voltage when accessories are turned on, in
> > particular the climate control fan?    This car registers
> > significantly lower on the voltmeter than at the battery.
>
> Yes, it's normal.  My '82 reads about 6v with each cycle of the turn
> signal.  The gauge is wired "after" a lot of high current devices and
> they tend to cause a voltage drop on that circuit.  Heck, my cigarette
> lighter used to wreak havoc with all 3 gauges, since it raised the
> ground it was attached to.
>
> This only applies to the cars with the underdash "fusebox."
>
> -- 
> Huw Powell
>
> http://www.humanspeakers.com/audi
>
> http://www.humanthoughts.org/
>