Check the fuses, check the bulbs but first, be sure the dash light dimmer control is not turned off.
The alternator is failing.
Be sure the brightness control switch is not turned off, Check the fuse, Check the bulbs.
Be sure the dash illumination dimmer switch is not turned off.
Are you sure you didn't turn the dimmer down
might be a fuse
Just a suggestion, check your trailer lights harness for corrosion. They were taking the dash lights down in my chevy.
The brightness control may be turned off, The fuse may be blown, The bulbs may be burned out.
Probably a blown fuse. What you need to find out is why the fuse blew.
There is a very good description if you click on the link on the right.
4x6 in the front dash
I have a 1991 Chevy surburan and it has no tail lights and no dash lights, all fuses are good
If you have no dash lights at all on your 1989 S10 Blazer, a blown bulb can be the problem. You should also check the fuse.