The action of the voltage 'stabiliser' means that there is 12v switching on
and off about once a second which is the supply to the gauge on the
light-green/green, I've never measured the voltages on the sender wire
(green/black). A 1973 senders measure around 35 ohms full and 300 ohms
empty, but there is quite some variation as gauges often need recalibrating
after a sender change.
It is not good news to ground the sender wire for long periods as it draws
significantly more current through gauge and stabilser than normal. You can
use a test-lamp connected to ground, and if you drive around a bit like that
with it connected to the gauge terminal (and the green/black disconnected)
and the gauge is steady then the gauge and stabilser are likely OK and the
problem is with the wire to the tank or the sender or the sender ground.
This ground should go to the main grounding point at the back of the
boot/trunk and often causes problems.
PaulH.
----- Original Message -----
From: nxhio xebeaio <Rmartin@yedtech.co.il>
To: Mg mailing list (E-mail) <mgs@autox.team.net>
Sent: Tuesday, August 14, 2001 4:30 PM
Subject: fuel gauge
> Folks -
> I am looking for a way to test the voltage coming from my fuel level
sender
> (at the sender) and the voltage getting to my gauge (at the dash).
> The fuel gauge has been acting funny (jumping from overfull to mostly
empty,
> reading differently every time I start the car, etc) lately and i'd like
to
> troubleshoot.
> I can use the multitester to make sure that what is coming out of the
sender
> is the same as what is coming into the gauge, but as far as knowing
whether
> the gauge and/or the sender is calibrated right, the best I can do is
> guesstimate.
> If anybody has ever made a chart of the voltage that the sender should
send
> and should cause the gauge to read F, E, 1/2, etc, I would be grateful to
> get it.
///
/// mgs@autox.team.net mailing list
/// (If they are dupes, this trailer may also catch them.)
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