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ray_mcavoy · 02-01-2023, 12:24 AM

How did you wire up the battery gauge using your new harness? Did you hook one side to positive and the other to negative? If so, that's the problem.

The battery gauges in these trucks are shunt style ammeters, not voltmeters. They need to be connected in parallel with a shunt wire so they can measure the current flowing in that wire. As you measured, the battery gauge has a very low resistance coil inside so connecting it up like a voltmeter (+ and -) results in a short circuit that blows fuses and/or burns out the gauge.

02-01-2023, 12:24 AM	#2
ray_mcavoy Registered User Join Date: Nov 2009 Location: Sherman, ME Posts: 2,373	Re: HELP! Electrical issue How did you wire up the battery gauge using your new harness? Did you hook one side to positive and the other to negative? If so, that's the problem. The battery gauges in these trucks are shunt style ammeters, not voltmeters. They need to be connected in parallel with a shunt wire so they can measure the current flowing in that wire. As you measured, the battery gauge has a very low resistance coil inside so connecting it up like a voltmeter (+ and -) results in a short circuit that blows fuses and/or burns out the gauge.