Fuel gauge question
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Junior User
Joined: Jul 2009
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Fuel gauge question
I'm having trouble with my fuel gauge. I ohm all my wires and everything is good. I made sure my sending units ground is good. I ohm my fuel gauge and I get 13.4ohms with my gauge set to 200ohms (with the cluster unplugged). When I plug my gauge cluster in and turn the key on I check the black wire (at the plug) that feeds power to the resistor? of my fuel gauge and oil temp and my meter bounces between 12v and 10v. When I unplug the cluster and check the black wire (at the plug) I get 12v steady. I have two gauge clusters and when I plug the second one in I get the same bounce in voltage. Is this normal?
Thanks for the help
Thanks for the help
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Junior User
Joined: Jul 2009
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I'm guessing the test light gives enough resistance through the bulb to make the gauge work. But why is the sending unit not doing it??? Some times electric stuff drives me nuts!! You would think it would be like math, there is always a correct answer. Just finding it, like with math, can be a little nerve racking. :P
MSEE
Joined: Apr 2004
Posts: 10,386
Likes: 35
From: Austin, TX
We need to start over. The test light business is not correct. When you do the ground test, you should unplug the bullet connector of the sending unit, and ground the harness-end of the connector to the screw that holds down the sending unit ground ring terminal to the crossmember. This should be done with the key on. The fuel gauge should peg full. Are you doing it this way?
Certified Thread Hijacker
Joined: Aug 2001
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The gauge should peg "full" when you ground the sending unit wire to ground.
The sending unit also opperates under a pulsed 5 volt feed and not a straight 12 volts.
The ohms for the sending unit (not the gauge) should more or less be in the range of approximately 8-12 ohms full and 70-73 ohms empty.
Josh
The sending unit also opperates under a pulsed 5 volt feed and not a straight 12 volts.
The ohms for the sending unit (not the gauge) should more or less be in the range of approximately 8-12 ohms full and 70-73 ohms empty.
Josh
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