Nina,
As you have seen in the diagram, regulated power from the voltage
stabilizer comes into the fuel guage (light green/green wire), out from
the guage (green/black) to the fuel level sender on the tank, through the
sender, then out on the black wire to ground on the chassis.
If your light dims and brightens as you move the float arm up and
down, that means that the potentiometer (variable resistor) is working.
The fact that grounding the green/black wire to the sender sends the
guage to 'full' means that the guage itself is working. ( Thats what the
potentiometer does when the tank is full.) If the guage still reads empty
when moveing the float up & down, using the standard circuit, that means
that there is too much resistance in the circuit, and the current flow
through
the fuel guage never gets high enough for the needle to move off of
empty.
The most likely culprit would be corrosion at the ground connector, or
in the ground leads from the tank sender to the ground point. The
corrosion wouldn't be in the lead from the guage, because the guage
reads full scale when the wire to the tank sensor is shorted ( assumeing
your doing that at the tank). Check that the spade lug ground connector
has good metal to metal contact with the chassis, and that the plug-in
connectors between the tank and the ground point are clean and free
of corrosion.
Good luck...
Harlan.
-----Original Message-----
From: Nina Barton <ninab@scoresheet.com>
To: mhartwig@cbu.edu <mhartwig@cbu.edu>; 'MG List' <mgs@autox.team.net>
Date: Tuesday, June 16, 1998 4:25 PM
Subject: Re: Fuel Tank sender
>At 3:27 PM 6/16/98 -0500, Mike Hartwig wrote:
>>Dan and others, a quick test to determine if your sending unit, gauge,
>>wiring, or combination is at fault:
>>
>>turn on the ignition and unplug your wire (not the ground wire) that
>>connects to your sending unit.
>>ground this wire and check to make sure your gauge reads full.
>>
>>When your gas tank is full and your sending unit works properly, you have
a
>>good ground connection, the sending unit will fulling ground, showing zero
>>ohms resistance. This resistance corresponds to a full reading on your
>>gauge.
>
>I can get this reading of full by grounding out the sending unit. Since I
>don't have anything but a test light, I can't check ohms or anything,
>however, the light bulb in the test light fluctuates in intensity as I
>check power at the sending unit wire. I've checked ground, but according
>to the wiring diagram the green/black wire doesn't go anywhere but to the
>gauge. What more should I check to make sure I don't have a power problem?
>Thanks in advance, Nina
>
>
>
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