CR - use the 'Diagnose' format provided on the www.autoMD.com website.
For example, how many miles are on the vehicle?
How long has the instrument panel (dash lights) been going out (not working)?
Does the dash lights (instrument panel) dimmer switch work - to adjust / change the light intensity?
What has been diagnosed or tested so far?
What are the conditions where the instrument panel lights will not work?
Have you already checked and cleaned the ambient (exterior) light sensor?
Have you at least inspected the fuses, wiring and relays for any loose connections and corrosion?
Some vehicles have individual LEDs that light the dash; however, even just a few years ago this wasn't necessarily the case. If your vehicle doesn't have an LED-illuminated instrument panel, it's likely backlit by several incandescent bulbs. If one of these burns out, a portion of the dashboard will be dark, while the rest is light.
If the entire dashboard is dark, chances are a fuse has blown. This is a relatively easy fix: simply remove the old fuse and replace it with a new one. If it continues to work well, that's great!
If it burns out again, it could signify that there is an electrical problem - requiring testing and diagnosis with these tools: VOM (volt-ohm meter) and electrical schematic, and probe / continuity tester.
Many drivers expect their vehicle to come with some sort of dashboard illumination adjustment feature, but finding it is another story. Here is where to look.
As might be expected, the knob to adjust the dashboard illumination can be found on the dashboard. Look through the opening in the steering wheel and you should see the knob sticking out near the top of the instrument cluster.
To make the light brighter, turn the knob to the right. To dim the light, turn it to the left. Keep in mind that the brightness can be adjusted when the headlights and parking lights are on.