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**damnyankee36** · 08-15-2017, 11:07 AM

Yes, you ground that terminal. There is "power" there, but it is after the coil in the gauge. It's the same thing as having 12 volts on one end of a relay coil and grounding the other end to energize it.

Look at the attached pic. You can see how each end of both coils are connected to 12 volts. The one on the left is already grounded. The right one is attached to the sender which varies the resistance from 0-90 ohms. 0 ohms being "ground."

08-15-2017, 11:07 AM	#13
damnyankee36 Senior Member Join Date: Sep 2002 Location: Alamogordo, NM Posts: 666	Re: Installed '90 GM Factory EFI tank, '72 Blazer Factory gas gauge is pegged past fu Yes, you ground that terminal. There is "power" there, but it is after the coil in the gauge. It's the same thing as having 12 volts on one end of a relay coil and grounding the other end to energize it. Look at the attached pic. You can see how each end of both coils are connected to 12 volts. The one on the left is already grounded. The right one is attached to the sender which varies the resistance from 0-90 ohms. 0 ohms being "ground." Attached Images