In the top center of my dash of my '76, I've got a control that the owner's manual calls an "Ideogram Illumination Intensity Adjustment Potentiometer". I don't know what this does.
I've also got what the manual calls a "Knob switch and rheostat for instrument cluster lighting" which adjusts the brightness of the lights in the instrument cluster--that one does what it is supposed to.
I'm in the middle of re-doing my dash, and I'm thinking about eliminating the "Ideogram Illumination Intensity Adjustment Potentiometer". Maybe I shouldn't because it has such a cool name...

Does anyone know what this controls?
Thanks,
-J