OK, you know those cheap Chinese icicle lights?

Does anyone understand enough about the circuitry to have an explanation as to why the first third of a string wouldn't work, but the rest of it does? I look at the wiring, and there seems to be a lot more than necessary (sometimes four in the strand, sometimes three, sometimes two). What's the deal?

I don't want to spend a lot of time on it, because I can replace them for a few bucks, but if it's something easy, it would be worth not having to run to Tarzhay for them.

Sorry, no bright ideas here. I actually had a similar problem with some of my icicle strings this year. I just gave up and bought new ones. Those lights are so poorly made, you're lucky to get more than one season out of them.

Try shaking them. It worked for me.

A common problem. The likely case is that they have the string separated into 3 sections where all the bulbs are wired in series, and then these are wired in parallel. Check for a loose bulb. With current bulbs, burning out the bulb will not put out the whole string, so that's not likely to be the problem. It's probably a loose connection in the burned out 1/3rd, most likely one of the bulbs being loosely connected.

This is what I deduced the wiring was when I spent several hours a couple weeks ago trying to salvage as many strings of partially functional lights as possible to decorate the Valparaiso University Chapel for advent.

I would have thought an engineer could diagnose
a simple little thing like some holiday lights.

yeah a segmented series parellel circuit.

you answered your own question when you looked at the wireing.

Rather than losing all of the lights, you lose some, so that you can troubleshoot a smaller section. What I do is I take one good bulb, and just rotate existing for known good right down the lights, since the contacts are too small for an ordinary multi-meter.

I was kinda surprised like anonymous.

also if they are white lightbulbs, it's generaly pretty easy to spot the burnout, just backlight the bulbs, and look for the one that is dark, or has a visible break in the filament.

Even if you have to go to the known good exchange, it shouldn't take more than 10 minutes, of repetative action to fix them.

or you could do what I did; wait. I put up two strings, only to find the outer half of each one dead (both strings had pretested fine). I said to hell with it and left it up, and behold! a Christmas miracle! They all worked the next day.

or you could do what I did; wait.

Ah, good old management by procrastination. My favorite management technique...

The Christian Science approach to repairs (wait, and God will heal it) doesn't always work.

Regards,
Ric

Aren't there several brands of those icicle lights that are recalled each year for burning people's houses down?