If your vehicle is showing interior lights don't come on when doors open, here are the most likely causes and the parts you'll need to fix each one.
The dome light switch was accidentally bumped or set to the 'Off' position instead of the 'Door' position. This frequently happens during interior cleaning or recent interior work.
A blown fuse will cut power to the entire interior lighting circuit. This often happens if a bulb shorts out or if wires were accidentally grounded during aftermarket accessory installation.
The filament inside the dome or courtesy light bulbs has burned out over time. If only one specific light fails to turn on, a dead bulb is the most likely culprit.
The physical switch in the door frame that detects when the door opens is stuck, broken, or corroded. If the lights work for some doors but not others, this switch is usually to blame.
If aftermarket LED bulbs were recently installed, they may be plugged in backwards. Unlike standard halogen bulbs, LEDs are polarity-sensitive and only work when inserted in the correct direction.
The computer module responsible for controlling interior electronics and theater-dimming lighting has failed. This is rare and usually accompanied by other strange electrical issues like power lock or window failures.