How to Troubleshoot Christmas Lights: Half of the String Is out
- 1). Check the connections in between strands to ensure they are properly connected to each other. Also check the plugs to ensure they are secure in the wall socket or power strip. Sometimes this is all you will need to get the whole strand working correctly.
- 2). Sweep your fingers gently over the lights on the strand. If any bulbs flicker, this indicates a loss of connectivity, meaning the wire in the bulb and socket are not connecting properly. Remove any bulbs that flicker, and replace them with new bulbs.
- 3). Look for any black bulbs on the strand that is only half lit. The presence of black inside the bulbs indicates that a bulb went out and was not replaced quickly enough to protect the strand from overload. This causes the remaining bulbs to burn brightly for a short time then to go out completely. Replace the entire strand, because even if half are still burning, they probably won't be for long.
- 4). Purchase a Christmas light bulb tester wherever Christmas decor is sold. The device tests each individual bulb quickly to see if it is burned out. Sometimes just one bad bulb can cause the entire or half a strand not to light properly. Replace any bad bulbs.
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