Error code E18 appears and the refrigerator interior light may stay on or off incorrectly, sometimes causing temperature rise.

Safety first: Unplug the refrigerator before working on the light assembly or door switch.

Steps:

• 1. Observe light behavior: Check if the light stays on when the door is closed (you can look through a gap or listen for a click from the door switch).
• 2. Test door switch: Remove and test the door switch for proper operation. Replace if faulty.
• 3. Inspect LED module: Remove the light cover and inspect the LED module for burn marks or discoloration. Replace the module if damaged.
• 4. Check wiring: Ensure the light harness is not pinched or shorted to the cabinet.
• 5. Control board: If the switch and LED are good but E18 persists, the light driver on the main PCB may be defective and the board may need replacement.