One of the most common electrical problems. It is usually caused by either
one or more diodes getting weak on the alternator, or bad connections in the
alternator - brown - solenoid - brown - ignition switch - white circuit. If
it does much the same when the headlights are used then it is either the
alternator or bad connections in the browns either side of the solenoid. If
the headlights don't have that effect then probably in the brown - ignition
switch - white etc. circuit. The light glows because there is a difference
in voltage between the brown/yellow at the alternator and the white at the
ignition switch, when ideally they should be at the same voltage at all
times (however differences of a tenth or so are inevitable and can be
ignored). If you get a bad connection in the ignition switch, say, the more
current you draw i.e. with turn signals or brake lights on, the more
volt-drop you will get in the switch (which causes it to get warm if not
hot) and so the voltage on the white drops below that of the brown/yellow,
causing the light to glow dimly. Measure the voltages on the brown/yellow
and the white while the light is glowing. If you see about 14.5v on the
brown/yellow but lower than this on the white then it is bad connections.
Check the brown at the alt, solenoid and ignition switch, and a difference
between any two adjacent points indicates a bad connection. If the brown at
the switch is good but the white is low then the problem is in the switch
itself. A difference between the brown and the brown/yellow at the alt
indicates an alternator problem. If you are saying this happens at idle but
not when the revs are higher then it could be the alternator, an earth-side
output diode open-circuit. All the diodes are in a single module so you
replace the whole module, not just one diode.
PaulH.
----- Original Message -----
From: "Hans Duinhoven" <h.duinhoven@planet.nl>
To: <mgs@autox.team.net>
Sent: Monday, August 09, 2004 10:00 AM
Subject: Glow in the dark
> When driving at night the battery lamp glows dim when the direction light
is
> blinking.
> It goes on and off in the blinker's tempo.
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http://www.team.net/the-local/tiki-view_forum.php?forumId=8
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