68 barracuda gauges, where is the Inst Voltage Regulator?

[bbeckwith]

I have read that many times a non-functional temp gauge is due to a faulty Instrument Voltage Regulator, that reduces 12 volts to 5 volts for the temp gauge and oil pressure gauge.  I have wiring diagrams and I see the temp gauge and oil pressure gauge both get the feed from the same source, (actually the feed goes to the temp gauge via the printed circuit board, and from the temp gauge to the oil pressure gauge.  I see no Instrument voltage regulator in the system.  Am I blind and just overlooking it on the diagrams?  It sure doesnt seem to be attached to the backside of the cluster like my Duster's is.  Should I be looking for another gauge as my temp gauge does not register anything at all but the oil pressure works fine, so I know it's getting juice.  I do have two spare temp gauges but dont know how to test them.  I have read some other posts about the voltage regulator and testing, but they dont seem to apply with this system.  What the heck am I missing?
I am currently rechroming my instrument cluster, and would love to fix this issue while I have the steering column (rebuilt the collar), and instrument cluster out of the car.  I would hate to have to pull it again later as the aftermarket air makes it a pita to pull the cluster out.

[Chryco Psycho]

you can test the guages by hooking 5v to the guage you need to trace the circuit back  to the regulator , I`m not fasmiliar with exactly where it is  in th eolder a bodys 

[Swedefish]

bbeckwith,I was looking for the same in my -67,later on I found out that it`s built in with the fuel gauge,that is if you got the rallye dash.But the Valiant got an extern voltage limiter,that is placed behind the instrument cluster.In the shop manual from -67 You can see the cluster from a Valiant,but nothing of Cuda instrument cluster.Strange  ::

[bbeckwith]

swedefish, I have an extra cluster I got from a friend that was damaged, think I'll go pull the gas gauge and see what's there.  Now another question, if the gas gauge functions fine, does that mean the volt limiter is ok?  I will have to go look on the circuit board, but I thought the line in went to the temp gauge first, then the gas gauge.  This has me confused.  gonna go pull the cluster apart and see.  Thanks for the heads up.

[Swedefish]

Had a look at a spare cicuit board that I have,there are three connections on the fuel gauge,first one for line in,second from sending unit,third
one for temp and oil pressure gauges,the supplay for temp and oil goes thrue the circuit board so maybe it`s there the probs are.I`m not sure but I don`t think the fuel gauge works if the limiter is broken,maybe CP have an answer on that.

[bbeckwith]

Thanks for the help Swedefish, I will hopefully get this sorted sometime this week.   :cool:

[Swedefish]

 :thumbs: Hope that it will be to any help
//Lelle