Oven displays F9 and may not start or complete a self-clean cycle; door may not lock or unlock.

Safety first: Disconnect power at the breaker. The door lock mechanism can move unexpectedly during powered tests.

Step-by-step checks:

• Inspect latch: Check the oven door latch at the front of the oven. Ensure it moves freely and is not bent or obstructed by grease or debris.
• Access lock assembly: Remove the top panel or rear panel (depending on model) to access the door lock motor and switches.
• Check wiring: Inspect the harness from the lock motor and switches to the EOC. Look for broken wires, loose connectors, or burn marks. Repair as needed.
• Test lock motor: With power disconnected, measure resistance across the lock motor terminals. Compare to service manual specs (typically a few hundred ohms). An open motor indicates failure.
• Check lock switches: Use a multimeter to test continuity of the lock and unlock switches while manually moving the latch. Replace the lock assembly if switches do not change state.
• Control board: If the lock assembly and wiring are good, the EOC may not be driving the lock circuit correctly and should be replaced.

Emergency door opening: If the door is stuck locked, consult the user manual for the mechanical release location or contact a technician to avoid damaging the door.