Wall console LED flashes twelve times and opener runs but lights do not function correctly (stay on or never turn on).

Safety first: Disconnect power before changing bulbs or accessing internal wiring.

• Use correct bulbs: Wayne Dalton openers typically specify a maximum wattage and bulb type. Replace with the recommended LED or incandescent bulbs that are "garage door opener compatible".
• Inspect sockets: Remove bulbs and inspect the sockets for corrosion, heat damage, or bent contacts. Clean or replace sockets if damaged.
• Test without bulbs: Remove all bulbs and restore power. If the F12 indication clears, one of the bulbs or sockets may be shorted. Replace bulbs one at a time to identify the problem.
• Board-level fault: If the lights stay on constantly or never come on despite correct bulbs and wiring, the light relay on the logic board is likely stuck or open. Replace the logic board.