I think the problem I will report is responsability of FSX. Some airplanes, such Boeing 737, Embraer 190 do not have their instruments iluminated by the light. So, it is quite impossible to fly at night. Other airplanes have ilumination OK. Any suggestion, please?

I have had some aircraft that didn't have working landing lights, but never panel lights. You probably should expect others to reply wanting more information. Are these related to freeware, payware or FSX default aircraft? Once you can share all the particulars to the aircraft, I am sure someone will be able to help you. I will be checking back because I surely would like to hear the answer!

Good luck - Rick

I have found that in boeing  PMDG 737 at night to see instrument panel go to Aft Overhead panel on turn on DOME lights. should correct your situtation

Intrument illumination needs to be coded into the gauges or model. If the developer hasn't done so, there is nothing you can do.