I have no idea what goes on in my attic between early January and mid-November, but whatever is happening up there, it’s not friendly to the Christmas lights. We use seven or eight strands of colored lights on the living (zombie?) tree we put up in the den each year and I tend to add two or three additional strands of white lights to the pre-lit artificial tree that goes up in the living room, so that’s at least ten strands I need each year.

Yet without fail, despite all the lights working fine at the end of the season, there’s an attrition rate of about 25% at the start of the next season. One strand will be totally dead. Another is half-illuminated. A third flickers. Yet another may seem fine during initial testing, only to go dead when jostled ever so slightly. (We still use incandescent lights for our indoor holiday décor, for the record. Outside it’s all about LEDs because once those things are up, no way I’d ever climb around fixing strands if one went out.)

So each year, I’m presented with one of three options: buy more strands of lights, check each and every bulb on the faulty strands by hand, or sell the house and move into a camper van endlessly rambling down forgotten blue highways out in the western states.

Ah, but now there’s a fourth option: I can grab my handy Light Keeper Pro, connect it to a faulty strand, pull the trigger, and have the problem illuminated for me, so to speak.

Holiday light strands usually fail because one bulb is damaged or broken, and the current can’t flow past said bulb because the circuit is broken. The Light Keeper Pro forces an electrical current to flow through an entire strand by creating a shunt that bypasses the bad bulb. The strand will light up, save for the problem bulb, which can then be popped out and replaced.

Using this tool before you hang any suspect lights is a good idea; using it to diagnose the problem with a strand you already put up so don’t have to spend an hour unwinding every wire on the tree and take down dozens of ornaments in the process? That’s a Christmas miracle.

Light Keeper Pro

Buy at Amazon$26

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