Oven interior light stays on all the time, even when door is closed and oven is off

Safety first: Disconnect power before accessing the switch or control board.

• Test door switch: Locate the door switch (usually near the door frame). Press it by hand and listen for a click. Test continuity with a multimeter; it should change state when pressed. Replace if stuck or not switching.
• Inspect actuator: Ensure the door correctly presses the switch plunger. Adjust or replace the actuator if misaligned.
• Control relay: If the switch is good, the lamp relay on the PCB may be welded closed. Replace the control PCB if the relay is stuck.