How do you find the bad bulb on Christmas lights without a tester?
Pull out one bulb at a time, and stick a piece of folded up foil into the bulb socket.
If the lights come on, you know that’s the bad bulb.
If they don’t, put the bulb back in and move on to the next one.
If you don’t have any replacement bulbs, you can leave the foil in until you do..
Is there a tester for Christmas lights?
Product Overview When there is a problem with holiday lights, the LightKeeper Pro Light Tester has the solution. Use it on most miniature incandescent light sets and pre-lit trees. Features an audible continuity detector that pinpoints the problem by tracing the circuit to the point of interruption.
Is there an easy way to check Christmas lights?
The easiest way to find faulty bulbs on incandescent Christmas lights is with a Christmas light tester. Simply bring the light tester close to each bulb. … If you have a non-contact voltage detector, bring the detector close to the wire section between each bulb to test for voltage.
Why does only half of my Christmas lights work?
If only half the strand is out… If half a strand is working and the other half is not, you probably have a loose or broken bulb. Start with the first unlit bulb and work your way down, wiggling them to check for looseness. If it flickers, that’s your cue to replace it.