Voltage limiter or lack there of

Littlejae

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Hi

I’ve got a 66 fury sport 383 727 console auto. On the three gauges on the left I’ve got no light and the gauges do not work properly. With that being said I’ve got good ground and 12v to the light circuits so I’ve changed bulbs and sockets with no luck. Now on to the gauges. Temp and fuel work with cluster out of the dash. When in the dash and the housing is grounded they don’t peg but go all the way left. Take them out of dash and they read properly. I was under the assumption that those gauges work on 6v not 12. I have 12. So ok let me check voltage limiter. Well I can’t find it. It’s not on either cluster nor is it in the fuel gauge which I currently have apart. Am I crazy here or what am I missing?? I done see any obvious shorts or wiring issues coming to the dash. Any help would be appreciated. Thanks
 

mr. fix it

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Hi Littlejae.
You're not going crazy just yet...

The voltage limiter is a resistor coil wire behind the fuel gauge on the fury.
It's a bizarre setup but that's what it is..
Not easy to get at to test or replace.

With 50+ year old tech, these resistors get corroded and thinner causing the resistance to increase which translates into gauges not getting enough voltage to power them accurately.

Check online google or here to see related repairs for this setup.

most will direct you to the plug in style limiter which isn't correct.
 

Davea Lux

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If the gauges are all pegging on the top end, the voltage limiter is probably fused or shorted. If you reference the wiring diagram, the fuel gauge has three terminals coming out of it. You can clip the leads that feed the limiter and wire in a replacement electronic unit to feed the gauges. There is a post someplace on this site on how to do this repair. The three terminals are labeled "I" terminal is the input power 12v. "S" terminal goes to the sending unit. "A" terminal powers the gauges from the limiter, including the gas gauge. If you clip the wire going from the "I" terminal to the limiter, this kills power to it. Use a loop connector and wire on the "I" stud to power the replacement limiter. it should have power from the circuit board. The "A" terminal should have a wire hooked to it coming from the limiter, if the limiter is shorted, this wire needs to also be disconnected. Be careful doing this so you do not damage the lead to the gas gauge. Use another loop connector from the "A" stud to the output on the replacement limiter. This should power all the gauges. Be sure to ground the case on the replacement limiter as it needs a ground to function. Back 25 or more years ago when replacement gas gauge/limiter units became obsolete and the electronic replacements were not invented yet, we used the limiter from a '70 Plymouth which is still readily available and wired those in.

Dave
 
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Littlejae

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Weird thing is the gauges don’t peg on the high side they actually go low and the don’t go all the way down. But when gauge cluster is removed from dash they work correctly. So grounding the dash cluster makes them inoperable.
 

Davea Lux

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Weird thing is the gauges don’t peg on the high side they actually go low and the don’t go all the way down. But when gauge cluster is removed from dash they work correctly. So grounding the dash cluster makes them inoperable.

The limiter is probably corroded then and not supplying enough voltage to power the gauges. You can take a voltmeter to check this. Put 12v to the "I" terminal, ground the cluster case. You shoud get about 5-5.5 volts from the "A" terminal if the regulator is working. Less if it is corroded or open.

Dave
 

mr. fix it

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Weird thing is the gauges don’t peg on the high side they actually go low and the don’t go all the way down. But when gauge cluster is removed from dash they work correctly. So grounding the dash cluster makes them inoperable.
Not reversing the voltage are you?
 

Littlejae

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No I’m not reversing voltage and as soon as I get done with these transmission lines I’ll get back on the gauge and do some more tests.
 

Littlejae

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Well instead of checking gauges again I decided I wanted to drive up the street and back for the first time in a year so I got this thing broke in and driving lol now back to the gauges and valve cover leak.
 
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