200tq low voltage

[SJ]

> From: Kurt Deschler <desch at alum.wpi.edu>
> Subject: 200tq low voltage
>
>
> Subject is an 89 200tq. Guage on dash displays 11-12V with the heater
> on high and the headlights on. Appro 14V with all accessories off
**** Check the voltage at the alternator output - with accessories on and
off.
In general, the alternator feeds a main wiring splice, to which the major
electrical components are connected.

It's possible that the wire feeding this splice is corroded or has high
resistance.
When you have no loads running the splice will read same as alternator. No
load means little current. Little current means low voltage drop across the
feed wire.

But, when you put on a heavy load, you get a high voltage drop across that
defective feed wire. High load means high current. High current means high
voltage drop. The alternator might read 15 volts, but the main splice will
read only 12 volts.


SJ
85 Dodge PU, D-250, 318, auto
85 Audi 4k - - sold but still on the road
88 Audi 5kq
90 Audi 100q