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jmanz69 · 03-19-2004, 08:08 PM

That wire going to the sending unit isn't a 12 Volt wire. It's a sensing wire. If you put 12 Volts on it, you probably blew your sending unit. The 12 volts goes to the gauge, then out at a lower voltage to the sending unit. The gauge reacts to how much of a voltage drop is on that wire thru the sending unit. Sounds like you fried it man. I would look for another sending unit. You can take yours out and measure with a meter from the terminal for the wire to the outside of the sending unit (ground) and see if there is 0-110 ohms when you move the float up and down. If there is, then you blew your gauge. Good luck.

Here is a pic of the wire diagram how it works.

03-19-2004, 08:08 PM	#12
jmanz69 Careful, they attack... Join Date: Aug 2001 Location: Waterford, MI, USA Posts: 1,107	That wire going to the sending unit isn't a 12 Volt wire. It's a sensing wire. If you put 12 Volts on it, you probably blew your sending unit. The 12 volts goes to the gauge, then out at a lower voltage to the sending unit. The gauge reacts to how much of a voltage drop is on that wire thru the sending unit. Sounds like you fried it man. I would look for another sending unit. You can take yours out and measure with a meter from the terminal for the wire to the outside of the sending unit (ground) and see if there is 0-110 ohms when you move the float up and down. If there is, then you blew your gauge. Good luck. Here is a pic of the wire diagram how it works.