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...