My Dash lights don't work when I turn on my headlights
The easiest way to pinpoint the cause of this is to first check that the dimmer on the dash is turned up. Next would be to check the fusebox. If a fuse is blown it is cheap to replace and fast. If the first two steps are fine then it might be a bulb that you might have to replace.
I would lean to a bad dimmer switch before the bulb idea. That's a lot of bulbs just going out at once
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