I have no lights in cabin, radio don't work and gas tank don't show gas level

how many volts on the battery?are all the connection clean,free of corrosion and tight,including grounds?

TEST ALL FUSES with a test light!

I had an 1992 toyota camry,,,I got problem...when I run the car for few minute,, the engine go off himself,,I check battery is ok..alternator is ok,,I replaced the main relay ..and I run again and still happend ...any adviced