Ignition warning light glowing - particularly if the brightness increases as
you increase the electrical load - is a classic symptom of alternator diode
problems. There are nine diodes in the 'stack' and depending on which
one(s) are gone and whether they are short or open determines what other
symptoms you have. These can range from discharging the battery whilst
parked, insufficient charge when it is running, excessive heat and noise in
the alt, to appearing to work OK. In the latter case you may find that the
max output of the alt is significantly reduced, which only shows itself when
running for long periods with a big load e.g. lights, wipers, heater etc.
In your case it sounds like it has stopped, or greatly reduced, charging.
With the engine running at fast idle check the voltage on a brown wire - you
should see around 14v. If you see less than 13 the alternator needs
replacing.
There can be other causes of battery discharging and horn and turn signals
not working, but I would start with the alt first with your symptoms.
PaulH.
----- Original Message -----
From: <DMKap@aol.com>
To: <mgs@autox.team.net>
Sent: Monday, September 18, 2000 2:53 PM
Subject: electrical problem..need advice
> My '80 B has developed an electrical problem in the last few days, and I
need
> a little help diagnosing the problem. I first noticed that the ignition
> light started to faintly glow while driving. then the next day, the horn
and
> turn signals stopped working. Also the new battery is not charging (or
> holding a charge or is discharging). Of course it sounds like a short
> someplace...but where do I start?? Everything was rewired about a year
ago,
> and I haven't had any trouble since. Thanks for the help !!!
>
> David Kaplan
> Lexington, KY.
>
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