[Kings-x59]

OK, if there is no interior light switch, check your fuses.
Check the bulbs. It'd be unlikely that they'd both burn out at the same time, however I can't say I know how they are wired. If they are wired in series like cheap christmas tree lights, one burnt out bulb kills the circuit.
If opening any door doesn't kick the lights on, most likely it's a fuse. If it turns out the fuse is blown, and a newly installed fuse blows as well, there's a short in the circuit. Most likely culprit is worn insulation abraded on metal somewhere that is grounding out.