>...Fitting a diode in the indicator lead to cure this is absolutely stupid -
>all you are doing is stopping your alternator telling you when it has failed
>completely, it would be far simpler to remove the light altogether. But the
>preferred option is to fix the real problem.
>
>PaulH.
Paul - and List -
Maybe it is ...absolutely stupid... but I can duck that one 'cause I'm not
the one who did it. At any rate, the offending diode is no longer there.
But even then I ask why, when the diode was still there, did the light
still come on brightly when switching on the ignition (as it is supposed
to), only to promptly quit when the engine started (again, as it is
supposed to)? Why did the diode not prevent it from lighting at all?
As I think about this, I may be starting to answer my own question.
Hopefully you can either verify or show me the error in my thinking. The
light simply indicates a voltage desparity between alternator output and
the ignition circuit, right? What if the alternator output voltage is
slightly higher than that (from the battery) at the end of the white wire?
The light would glow then too, right? But since that is not due to an
alternator fault, we don't need that information. So, (1) can we defend
that in-line diode on the basis that, since it allows current flow in one
direction only, it is simply keeping the light off when the alternator
output is greater than the ignition circuit, and (2) is there a type of
battery defect that can lower its output enough to cause this problem (the
glow is rpm-independent)? I would presume that if this is due to line loss
from poor contact in a bullet connector or the ignition switch, that in 23
years, total failure would have resulted.
I suppose another answer that it apparently is charging - enough to be
functional even - but not as much as it should. This battery, of
indeterminate age when I bought the car in '91, still spins the starter
faster than any of my other Bs.
But really, despite the fact that we all know the light isn't supposed to
glow, if the car is operated that way without electrical failure for over
two years and perhaps 20,000 miles - mostly commuting at hours when the
headlights are on - is it not unreasonable to presume that there is no real
problem?
Oh-oh - I should never talk that way - lest tomorrow morning I should go
out to start my B and find the battery dead.
TIA
Allen
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