Power to gauge lights in this photo....
 

My gauge lights (and also accessory gauges) working briefly and intermittently when I first got the car.

Not worked since.

Like most, I get the gen light when starting, working turn signals, high beams indicator.
(my clock was working- has the constant power line- but has quit, not sure if the 10 year old quartz conversion died, tracking other stuff down first)

Just not the instrument lights.

My ground is good.

I changed the rheostat fuse (cheap)

changed the bulbs (almost as cheap)

next step was going to be a new headlight switch in case of a bad rheostat
(not so cheap, about 75$ delivered since a hideaway car)

if that did not work,
was going to do a new printed circuit (about 100$ delivered,
plus the pain of pulling the dash/gauge cluster)

but...

while trying to sort out the power,
is the gray wire power to the lights supposed to come from the steering column connector? that's the impression I get from the wiring diagram, but its like a star with power to printed circuit, heater lamp, raido lamp, lighter lamp, etc.

I found this trying to sort it out?

http://i649.photobucket.com/albums/u...r/DSCN4156.jpg



http://i649.photobucket.com/albums/u...r/DSCN4157.jpg

If this is supposed to go to the column, how do I yank the connector off the column to hook up the errant gray wire?

Thanks for any info.

Stop what you're thinking and start over
 

A 12 volt test light is all you need to diagnose this.
Lets start at the fuse box: Tail light fuse also powers dash lights. Power comes from the tail light fuse to the headlight switch. When the headlight switch is pulled on, dash light power goes through the rheostat, behind the knob, then back to the small inst fuse in the fuse box. Then the gray wires come from the small fuse to the instrument lighting.
So dash lights have two fuses in the fuse box, one before the headlight switch and one after.
All the gray wires are dash lights. The one that went up the steering column, would've been for shift indicator on cars with column shift automatics. Or possibly lighted key on 69 up models.

So with your test light check both ends of the tail light fuse for power. Turn lights on and check both ends of the little instrument light fuse for power. If it's working up to there, hold the test light on the small fuse and twist the headlight knob. The test light should bright and dim like the dash lights. From there move to gray wires and instrument light bulbs checking for power with your test light.
Only the dash lights in the instrument cluster use the printed circuit for power supply and ground. Heater controls, the wire that goes up the column (shift indicator), etc., aren't affected by the printed circuit.

If you lose power anyplace while testing, check the last components power came through. The headlight switch can work and rheostat spring be broke, rusty, corroded, and the dash lights won't work.

You can use a jumper wire from the tail light fuse to the instrument light fuse to by-pass the headlght switch if it's suspect.

Check it out again and post back. Don't buy parts till you need them. everything can be tested before replacing.

------------------------------------------------------------
"If this is supposed to go to the column, how do I yank the connector off the column to hook up the errant gray wire?"
-------------
Each wire terminal in the plastic connector has a tab that you can release with a pic (paper clip) and slide the terminal out of the plastic connector. Then you can pull the turn signal switch and the wires will slide up and out of the column. Tie a stout string on the wires before you pull them out. It makes pulling new ones back down alot easier.

I don't think this is anthing you need to worry about with the dash light problem. Maybe somtime else, just not now.

Thanks,
I guess this is way more accurate than looking at the fuses.

I have power on both sides of the tail light fuse.

On the little 4 amp fuse, with the lights on, and the headlight knob turned most of the way counter clockwise, I have light. It gets brightest when fully to counter clock wise. And light when almost fully counter clock wise, but does not dim and bright the whole rotation like it should.

And, no light on the left of the fuse. I already replaced it, but will see if I have another one that size.

Thank you.

Well, you nailed it. I feel dumb as I alreay replaced the fuse. I wonder if while changing it I put in the old one and threw out the one I thought I put in.

I could not read what the new fuse said, but its the only one that small I had, and smaller than the 7 1/2 A one I can read. I put it in, and same deal as with the test light.

I get almost all the way counter clockwise and I have guage lights.
I turn all the way left and they stay on and click (which I think would also turn on the overhead dome light if that bulb was not burned out).

I had the dome light working (with one finicky door jamb switch that sometimes needed a wiggle for it to stay on) but need to change it again.

Anyways, thanks again. I will always go by my test light on the fuses instead of looks from now on. I checked under a lit magnifier glass and it is bad to the eye, just not to the bare eye. Man, and to think I changed it months ago and thought that was good.
I appreciate you taking the time to answer.

With that bare gray wire, make sure it doesn't touch anything metal.
It will blow a fuse.
Possibly what happened while you were looking around under there?

At least tape it up.

:)

That looks like a dash light wire.Some one before may have cut it and used it for lights in an aftermarket set of gauges......JB.

Yep, I am not sure.
Shift light? Key alarm, Horn?

I have taped it off. I do have another gray going to a set of gauges.
Thanks.