97 sentra dash and interior light not working

[ZeNkI S14]

I have a friend that owns a 97 sentra 4 door and the dash light does not come on when you engage the headlights. the interior lights do not come on and including the automatic stick lights does not come on. Let me know if it is something easy to repair. Name me the things that could cause it to go out like that. thanks.

[Japtech947]

When did the problem occur or start and does the vehicle have an aftermarket radio that has been recently installed? Also could be just a bad illumination switch or what they call a dimmer switch that controls the dark or brightness of the dash lites etc,.