indicator lights and voltmeter

[Kevin Page <kbpage@richmond.infi.net>]

Good job on pulling off an otherwise towable situation.  Here's what I have done
to advance warn me of troubles with my M19 12 volt system.

Thanks to Wray Dudley for teaching the term on board "idiot light" and "volt
meter".  I have both on my car's 12 volt system.  Instead of the big 12 volt bulb
to provide the field draw for the alternator (as I understand it), I use a 12 volt
relay that some of the lights (strobe, ditch lights, fans, and others) and the
wipers are connected to.  If the alternator does not work, I don't have the
additional lights, wiper motors and other non essentials.  I did jump to direct
wiring around the relay on the single head/2 tail marker and brake light so that I
could have those when or if I break down or coasting dead to a stop if the car
won't run (safety).  The "idiot light" (my favorite indicator) is also wired to
the relay that only powers up when the alternator is making current.  It is an
orange dash indicator type light from the auto parts store (about $2.50 or so)
that is flush mounted on the air shroud inside the cab behind the condensor (hole
drilled).  The light tells me at a glance everything is okay (that's the idiot
light side taken care of).  The volt meter, which WD gave me as a Xmas gift (okay,
it's a way to force me into it) gives me a good feeling of how much voltage the
alternator is producing.  It is back lit with a switch also connected to the
relay...at night if the back light of the voltmeter goes out and the orange light
blows the bulb for some reason, I'm still covered with an "idiot light"
indication.

On the stop light issue.  Below the orange alternator indicator on the shroud is a
red indicator light (identical design just different color) that is wired into the
brake light switch  so that I know the brake light circuit is activated.  If you
really want to do it right, you could, I guess(I am not an elec. engineer), series
it through the brake light bulb and know exactly if the bulb is burning.  I didn't
want to run the extra wiring so I just ran from the switch. 30 minutes and about
$10 and you're in the two "idiot lights" and about $15 more you're in the
voltmeter.  If I remember right, the 12 volt relay is a horn relay (high amp)  for
an old style car and works well.   Good luck.


Kevin Page

ShellScale@aol.com wrote:  A voltmeter confirmed that my alternator had

> failed and the headlight, strobe, brake light, and markers had drained the
> battery.