instrument voltage regulator
 

IVR provides fluctuating voltage to gauge cluster in order to run the fuel, oil, temp an ammeter. When the gauges are disconnected, the proper voltage is there, connect gauges and its gone. Gauges read good according to my meter (even swapped gauges with no luck). Can't find any grounds to cluster housing or anywhere else.
In the prcocess of insulating gauges ad cluster as good as I can, we'll see.
Any thoughts?

Re: instrument voltage regulator
 

Bad ground ?
Bad connection, dropping so much voltage the IVR can't compensate ??
Thats a tough one.

Rod

Re: instrument voltage regulator
 

What are we working on?

Re: instrument voltage regulator
 

Sorry, 70 fastback, 351w.

Re: instrument voltage regulator
 

To clarify: When the IVR is unconnected to the gauges, and running, you get a current of x-y value? (I forget what it is for a 66, and don't know for a 70)
Then you connect them and the ivr is dead, i.e no voltage on the *input* side? Or is it just that the voltage drops?

Re: instrument voltage regulator
 

The IVR is supposed to provide a fluctuating 5 volts (flucutes due to opening and closing of IVR) to the gauges. The 5 volts is there until the fuel and or temp gauge is introduced to the circuit. Then the voltage disappears. i can't find any grounds, gauge cluster is isolated from rest of car so i feel the problem is definately within the cluster.

Re: instrument voltage regulator
 

I would say just replace the printed circut board. Theres a couple of companies that sell them. :confused:

Re: instrument voltage regulator
 

unfortunately I have, the old one was fried. Just have to keep looking.

Re: instrument voltage regulator
 

So...If it works ok jumping those gauges, i.e. connecting the input and output for a particular gauge, ....
Maybe the sheet is grounding somewhere? Dunno, thats odd.

Re: instrument voltage regulator
 

Thanks for your input, think I finally nailed it. Don't know what but something was grounding out to gauge housing. Sprayed it with an insulating laquer and that seemed to fix it for now. We'll see.