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Old 04-05-2007, 10:12 PM
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Doc here,

If you HAD a 6 Volt gauge and YOU wired it to 12 volts, It's probably damaged now..replace it.

Or wire it back as 6 volts and do this:

Originally Posted by docvette
To test your sender, remove the sender wire, and watch the gauge, it should peg at full, If it does, then ground the sender wire, it should peg at empty or opposite the last reading, If you have this the system is whole and working.
IF you are lucky it may have survived.

You CAN NOT accurately test ANYTHING with a test lamp..(except to know power comes from somewhere through the lamp to ground..) USE a meter. Most likely you were seeing a path to ground through the meter or the sender wire lighting the lamp..but you can't tell without using a meter..

The SENDER wires NEVER have power on them for Fuel gauges (like putting a 12 volt fuse on 50 sticks of liquid dynomite..) FUEL SENDERS are always referenced to ground through a potentiometer..

Originally Posted by docvette
The Sender wire is a RESISTANCE to ground through the sender which IS a Variable resistor mounted on a float aparatus..The higher the float arm moves up, the more resistance (or less depending on the sender configuration) the more resistance the gauge See's, the more the needle drives upward..( "F" ) ..the lower the float, the reverse becomes true.. ( "E" )..

I'd wire the gauge back to the 6 volt config, and try the above sender test..if it is dead (no meter movement at all) ..get another gauge you hosed it..If it pegs the sender wire is shorted (or open) ..find the short / open and fix it..

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