Dash lights out in my '72 S

[jonstringer]

I just got my cutlass s in my possession recently, so i'm finding little problems here and there. A big problem is that my dash lights are completely out. Even my console shifter lights are out. The blinkers indicators, and brights indicator work, but that's it. All of the gauges work properly, just the back light is out. Any experience with this? Idea of what it could be? I have checked the fuses, and they are all new.

[Oldsguy]

It may be the multi-function light switch, you know the part that rotates to increase/decrease cabin light intensity. Or, it is possible you have a damaged wire to the back of the dash or a broken run on the dash circuit board.

[Lady72nRob71]

My guess is also that the rheostat on the light switch is defective.
They are easy to burn open if overloaded and the previous owners could have tried to hook something up to it that drew too much power...

Use a volt meter to trace the voltage back on the gray wire back to the switch. The switch is a bit of a PITA to change but I have done it. They are easy to find at most parts places.
If you do change it, be sure to change the most-likely-burned-out bulb behind the "Lights" wording above the switch. This 1445 bulb is in a small cylinder between the dash and the switch. Otterzone should have the bulb.

The light switch knob itself is a bit tricky to remove, from what I remember also. The manual did not describe the procedure right...
Holler if I can help more.

[jonstringer]

thank you for your help. i'll dive into it and let you know what i find.

[cutlassinvt]

if you do find out what happened, could you post it? i have the same problem with my 70, had to run the interior lights on a toggle switch

[Lady72nRob71]

Okay, I totally forgot about the fuse for the instrument lights.
I looked at the manual last night...

The gray wire from the dimmable lights go to a 4 amp fuse in the fuse block. The wire from the other side of that fuse is dark green and goes to the light switch rheostat. Trace these back to the light switch with a volt meter.

Check that 4 amp fuse in the fuse block. If it is bad, replace it. If good, make sure it is 4 amp. If larger than 4 amp, I would suspect the previous owners blew the fuse, upped it, then blew the rheostat. If the latter, the light switch needs a changing...

[cbogartjr]

Hi Rob. Just a follow on to this thread and a tread I posted earlier. (You helped me with a turn signal problem on my 67 442). The knob for the light switch comes out pretty easy as long as you push the small spring button ( on the bottom of the switch asm) as you pull the knob.

Ok, the dash bulbs...what is the bulb number and were can I get them?

I had to do some work on my dash circuit board. My dash lights didn't work. I had to resolder the pins. Vertually every pin was loose and I couldn't get continuity from many of the pins to the bulb. After resoldering and cleaning the pins to the board, cleaning the corrosion off the bulb ports, and cleaning the corrosion on the bulb sockets, I am getting perfect continuity every where. Continuity on the bulbs is ok, but since I have the dash out, I will replace them...thus the bulb number. Thanks for you help.

[joe_padavano]

To add to this thread, I've had the rheostat go bad just from normal wear and the dash lights would not work. I've also had a situation where the dash light fuse would continually blow when I went over a bump. It was a very frustrating to find, but ultimately it turned out to be the feed wire for the under hood light. Since I didn't have the light, the pigtail hung down and shorted out on my headers. It would bounce into that position on certain bumps.

[Lady72nRob71]

Originally Posted by cbogartjr

Ok, the dash bulbs...what is the bulb number and were can I get them?

I had to do some work on my dash circuit board. My dash lights didn't work. I had to resolder the pins. Vertually every pin was loose and I couldn't get continuity from many of the pins to the bulb. After resoldering and cleaning the pins to the board, cleaning the corrosion off the bulb ports, and cleaning the corrosion on the bulb sockets, I am getting perfect continuity every where. Continuity on the bulbs is ok, but since I have the dash out, I will replace them...thus the bulb number. Thanks for you help.

It makes good sense to replace them all while the dash is apart, as one will naturally fail as soon as it is back together.
The wedge-base bulbs should be #194 or #168. (Keep in mind I do not know much on the 67 models)...
The owners or service manual will give exact #s for each bulb. On my '72, the regular gauge illumination was from #194 bulbs, but i went to the #168s, as they are brighter (but have less service life).
The indicator lights should be all 168 in my opinion, so they are visible on bright sunny days...
Both of these bulb numbers are available at your local auto parts stores or even Sears or walmart...

Let me know if you still cannot get your dash light to work.

[cbogartjr]

Thanks Joe & Rob. Will do. I am replacing the headlight switch also. Thanks again....

[Lady72nRob71]

Originally Posted by cbogartjr

Thanks Joe & Rob. Will do. I am replacing the headlight switch also. Thanks again....

If you have a little light bulb that lights up the "lights" word above the switch, change that bulb also while you have it all apart. I think it is a 1415 bulb (at auto parts store only). Not sure on your model year though... I do remember fondly that the 72 HL switch removal required 3 shrunken hands...