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**pjmoreland** · 12-01-2005, 11:51 PM

I don't remember all the different things you have already checked on the fuel gauge, so I'll start from the beginning just to see if I can add anything that might be useful.

The pink wire provides power from the fuse panel to one terminal on the fuel gage. The tan wire provides a connection between the other terminal on the fuel gauge to the sender in the tank. The sender connects the tan wire to ground, through a variable resistor.

It seems to me that your problem is going to be one of three things:
1) Bad wiring
2) Bad sender
3) Bad gauge

The first thing I would check would be to make sure the wiring is good.

Power Wire (pink) -- You said that the pink wire has 12 volts on it. I'm guessing that maybe you measured the 12 volts at the connector that plugs into the back of the gauge panel. I would take that one step further and make sure you have 12 volts on one of the two terminals that are on the back of the fuel gauge. You can follow the trace on the printed circuit board from the pink wire to the gauge to see which terminal is connected to the pink wire.

Signal Wire (tan) -- Disconnect the tan wire from the sender (behind your seat). Use a test light or an Ohm meter to make sure the end of the tan wire that you just disconnected from the sender has a good connection to the terminal on the fuel gauge that is connected to the tan wire.

If your wiring all checks out ok, then I would test your fuel gauge next. With the tan wire still disconnected from the sender, your fuel gauge should be pointing all the way one way (I don't remember which way). Then touch the end of the tan wire to a known good ground, and the gauge should move all the way the other way. If the gauge doesn't move, then I'm guessing there is something wrong with the gauge. If it does move, then I'm guessing there is something wrong with your sender.

You could test your sender by removing the tan wire from the sender, and use an Ohm meter to measure the resistance between the terminal on the sender and ground when the tank is empty. Then go fill your tank up and measure the resistance again. I have no idea what the two resistance readings should be, but at least they should be different from each other. Somebody else will probably have an idea of what the two resistance readings should be.

Good luck getting it figured out. It's a pain to have to keep track of how many miles you have driven since your last stop at the gas station.

12-01-2005, 11:51 PM	#7
pjmoreland Senior Member Join Date: Jan 2005 Location: CA Posts: 6,236	Re: Giving it one more try I don't remember all the different things you have already checked on the fuel gauge, so I'll start from the beginning just to see if I can add anything that might be useful. The pink wire provides power from the fuse panel to one terminal on the fuel gage. The tan wire provides a connection between the other terminal on the fuel gauge to the sender in the tank. The sender connects the tan wire to ground, through a variable resistor. It seems to me that your problem is going to be one of three things: 1) Bad wiring 2) Bad sender 3) Bad gauge The first thing I would check would be to make sure the wiring is good. Power Wire (pink) -- You said that the pink wire has 12 volts on it. I'm guessing that maybe you measured the 12 volts at the connector that plugs into the back of the gauge panel. I would take that one step further and make sure you have 12 volts on one of the two terminals that are on the back of the fuel gauge. You can follow the trace on the printed circuit board from the pink wire to the gauge to see which terminal is connected to the pink wire. Signal Wire (tan) -- Disconnect the tan wire from the sender (behind your seat). Use a test light or an Ohm meter to make sure the end of the tan wire that you just disconnected from the sender has a good connection to the terminal on the fuel gauge that is connected to the tan wire. If your wiring all checks out ok, then I would test your fuel gauge next. With the tan wire still disconnected from the sender, your fuel gauge should be pointing all the way one way (I don't remember which way). Then touch the end of the tan wire to a known good ground, and the gauge should move all the way the other way. If the gauge doesn't move, then I'm guessing there is something wrong with the gauge. If it does move, then I'm guessing there is something wrong with your sender. You could test your sender by removing the tan wire from the sender, and use an Ohm meter to measure the resistance between the terminal on the sender and ground when the tank is empty. Then go fill your tank up and measure the resistance again. I have no idea what the two resistance readings should be, but at least they should be different from each other. Somebody else will probably have an idea of what the two resistance readings should be. Good luck getting it figured out. It's a pain to have to keep track of how many miles you have driven since your last stop at the gas station.