Can't see!

[Apruitt9]

10 Silverado LT, gauge lighting works as it should during the day, adjustment works as it should as well. But when it gets dark, they go out! No lights on my speedo or tach, lights still on for radio, HVAC, etc...those two gauges only. Ambient light sensor or? Lights worked as they should when I bought the truck about 6 months ago but slowly got worse, now nothing at night! Also, the overhead dash lights won't come on unless you open the door, will not come on if you push button to turn on!?!?

[jorgef4x4]

Check ambient sensor circuit and dimmer switch power.  Circuit for ambient sensor attatched.