Instrument (guage) voltage regulator.

[PlumCrazy]

Just so you are aware, everytime you "pop" those gauges with 12 volts you are causing some sort of damage to them.

[MEK-Dangerfield]

The fuel gauge not being connected would not be an issue.
You have tested the IVR & gauges & they seem to be good.
This would be my approach.
A. With ignition ON check that 12volts is getting to the IVR. With the panel out you may not have a ground for the IVR to operate so provide a temporary ground if needed.
B. Check that voltage is getting to the gauges from the IVR.
C. Ground the sending units wires, the gauges should peg. Be sure the motor block has a good ground.
With each of these steps taken & gauges work the only thing left is the sending units.

I really like option "C" here. On a spare set of gauges I have here, the gas gauge is at the end of the daisy change that also goes to the temp., and oil pressure gauges. If the gas gauge works, the regulator can't be at fault here. Be sure the gauge pod is screwed into the dash, or firmly grounded when you try any tests.


  Mike

[PlumCrazy]

I believe he is doing his on his SE, if so the gas guage has nothing to do with the IVR on the back of the dash.

[MEK-Dangerfield]

I believe he is doing his on his SE, if so the gas guage has nothing to do with the IVR on the back of the dash.

OHHHhh, Crap, 


  You are right. The gas gauge on S/E's get their power from another source. UGH, I forgot about that. 


  Mike

[DAYLEY/CHALLENGER]

Just to throw another kink in the picture........this is a 73 dash.....gas guage is in line.....I may have to start over....  Hey Wade ..  With the dash back in the car now I had my son watch the guage as I grounded each wire from the sending unit.  Nothing.  However i connected the oil pressure wire to the positive post on the battery (only a senond) and it moved.

[MEK-Dangerfield]

Just to throw another kink in the picture........this is a 73 dash.....gas guage is in line.....I may have to start over....  Hey Wade ..  With the dash back in the car now I had my son watch the guage as I grounded each wire from the sending unit.  Nothing.  However i connected the oil pressure wire to the positive post on the battery (only a senond) and it moved.

Was the key in the "on" position while you grounded the gauges?

  Mike

[Bullitt-]

However i connected the oil pressure wire to the positive post on the battery (only a senond) and it moved.

Don't know what to make of this other than it proves the circiut is complete.
The fact that it is a '73 cluster changes nothing tha i'm aware of.

[DAYLEY/CHALLENGER]

Hey Mike , the switch was on..........

[MEK-Dangerfield]

OK, I'm running out of brain cells now. 

 The year of the gauges does NOT matter here. Have you painted the engine block? Maybe the temp and oil sending units are not making a good ground contact to the block?


  Mike

[DAYLEY/CHALLENGER]

No painting the engine yet...I will check the grounds though...Aint life a puzzle??