Dash illumination not illuminating

[ubsplat]

Wondering if anyone has any ideas. My dash board illumination just up and quit working one night. I checked all the fuses but they seem good.
I tore apart the dash and replaced all the led's, several of which were clearly blown, but when put back together it worked the same. All the small led's, for dummy lights and turns signals etc, function normally but the large illumination lights don't go on when the headlights are activated. Could it be a bad headlight switch or is there another circuit in the path to the dashboard I need to check. Any help is greatly appreciated.
Thanks.

[timd]

My 2002 Ranger has a dimmer/dome light switch on the dash. Could be the wiring to it or the dimmer/switch itself.