Opel Corsa 1992: Interior alhumbrado problems

It seems I'm having nothing but electrical problems lately. Now, when I turn on the parking lights or the headlights, the instrument panel lights go out (tachometer, clock, etc.). Any ideas on how to fix this?

Thanks

If your car has a control for adjusting the instrument panel brightness, that's probably the problem.

You haven't told me if it's a Corsa A or a Corsa B, and I assume you've checked the two 10A fuses (red) with the parking light symbol and that they're good. If they weren't, in addition to the issue you're experiencing, the position of the instrument panel on one side (left or right) would also be faulty.
If it is a Corsa B (the round one), the instrument panel brightness control is next to the headlight tilt control, below the light switch and above the fog light buttons, to the left of the steering wheel.

I hope this helps.
Best regards.