Cool How To Check Christmas Led Lights References. Each year, look for signs of damage, including frayed wires or cuts or cracks in the wire sheathing along the whole length of each strand. Web first, remove a bulb from an unlit section of your lights.

Web most multimeters can also be used to test continuity, which is essential for testing christmas lights. Updated video that addresses some people's feedback such as not. Simply inspect each bulb and look for any that appear to be dimmer or not lit at all.