1955 12v gauge wiring

[Pete986]

I have a converted-to-12v '55.
I recently had to take the dash out to repair the odometer / speedometer. I guess I goofed up, during re-installation, because now the FUEL and TEMP gauge are both pinned all the way to the right.
I did some internet searching, but my problem is, every diagram I see shows gauges with two terminals. Mine both have THREE terminals.

I'm afraid if I keep trying different configurations, I'm going to wind up burning out wires, or damaging the gauges.

Does anyone have info or a picture of proper wiring for 3 terminal gauges?

This page contains affiliate links for which I may be compensated. As an eBay Partner, and Amazon Associate I may be compensated if you make a purchase at no cost to you.

 

[doug7740]

1955, 1956 and 1957 Thunderbird fuel and temperature gauges are 2 terminal gauges, not 3 terminal gauges. You have the wrong gauges in your car. Did they work before you removed the dash?

doug7740
1955 Thunderbird Blue.

 

[seatramp]

I have a converted-to-12v '55.
I recently had to take the dash out to repair the odometer / speedometer. I guess I goofed up, during re-installation, because now the FUEL and TEMP gauge are both pinned all the way to the right.
I did some internet searching, but my problem is, every diagram I see shows gauges with two terminals. Mine both have THREE terminals.

I'm afraid if I keep trying different configurations, I'm going to wind up burning out wires, or damaging the gauges.

Does anyone have info or a picture of proper wiring for 3 terminal gauges?

Sounds like gauges are reverse wired. I just rewired the engine and dash of my 56 and got the wires backward on the fuel gauge. just reversed the wires and everything is back to normal. I don't know what the third wire on the gauge is for, if the conversion gauges aren't "stock" they may have built in back lighting thus the need for the third wire (if so it should connect to the dash light wiring). Per the ford electrical manual One wire (black-green) to each the gauges should be 12v from the ignition switch accessory terminal going to the gauge terminals closest to the speedometer. One wire goes from the temp gauge to the sensor on the engine (red-white). On the fuel gauge yellow wire goes to the tank sensor. You can check the gauges using 3vdc (two flashlight batteries in series) and should get a reading of about half the gauge) (works for either gauge)

 

[dmsfrr]

Some of the after-market / replacement gauges have 3 wires.
Example photos attached.

 

[doug7740]

Sounds like gauges are reverse wired. I just rewired the engine and dash of my 56 and got the wires backward on the fuel gauge. just reversed the wires and everything is back to normal.

The fuel and temp gauges will work on 6 or 12 V and are not polarity sensitive.

doug7740
1955 Thunderbird Blue