Regarding strings of LEDs

Hard to tell from the photos, exactly what order in the string, the sections aren't lit.  The string MAYBE wired that a section is in series, while a number of sections are connected together in parallel.  Otherwise if just in parallel check each bulb that is not lit.  If pure series none would be lit.  Hopefully one of the EE's on the forum can check my answer.

the curse of the Christmas lights Joe. I've done a lot of complex and intricate wiring over the years as an electrician.

Christmas lights get me every time. I throw them out and buy new when they don't work.

Except I scrounge the LED's first now.....

LED lights do not last forever.  I know a couple of folks that had 10 plus year old expensive artificial Christmas trees with many built in LED lights out.  They both bought incandescent mini Christmas tree light strings at Walmart and installed them, giving up on LEDs.  They can still get spare bulbs for incandescent mini Christmas tree lights.  I have several packages of 12v and 7v mini Christmas tree light bulbs as I use the to light my buildings on my layout.

Charlie

@Choo Choo Charlie posted:

LED lights do not last forever.  I know a couple of folks that had 10 plus year old expensive artificial Christmas trees with many built in LED lights out.  They both bought incandescent mini Christmas tree light strings at Walmart and installed them, giving up on LEDs.  They can still get spare bulbs for incandescent mini Christmas tree lights.  I have several packages of 12v and 7v mini Christmas tree light bulbs as I use the to light my buildings on my layout.

Nothing lasts forever, but an LED should last longer than you'll need it.  However, if the LED is abused by excessive current or reverse voltage, it's life can be sharply curtailed.  Also, many times when you see and LED out, it's the associated wire and/or power supply that is failing, not the LED.

As John said, in most cases its a matter of electrical contact and not the LED itself.

Often removing the LED and reseating it does the trick.

Finding the LED with the bad contact is another story!

Usually, there are two or more sections of the circuit in parallel. Each section has LEDs in series. The sections can be identified by the fact that only two wires run between sections. Within each section there are three wires between LEDs.

If you have more patience than I have, you can use a non-contact voltage detector to find out which socket is not passing current to the rest of the bad series of LEDs.

Or you can just remove and then reseat every one of the LEDs in the bad section!!

If you are extremely frugal and using the lights indoors, you can just cut out the bad section (at one of the two-wire junctions) and rejoin and shrink wrap the cut wires.

Joe, my advice - buy a new string of lights!!!

Jim

@RSJB18 posted:

the curse of the Christmas lights Joe. I've done a lot of complex and intricate wiring over the years as an electrician.

Christmas lights get me every time. I throw them out and buy new when they don't work.

Except I scrounge the LED's first now.....

Yup one hundred percent in agreement. One year one set in the middle of the tree was Dead, all I could here was you have an electrical engineering degree, you commanded a warship can’t you fix the lights? My response was Christmas lights are the dark arts in electricity. Buy new……….

@ThatGuy posted:

Yup one hundred percent in agreement. One year one set in the middle of the tree was Dead, all I could here was you have an electrical engineering degree, you commanded a warship can’t you fix the lights? My response was Christmas lights are the dark arts in electricity. Buy new……….

🤣🤣🤣🤣🤣🤣

Well said. 👍

@ThatGuy posted:

My response was Christmas lights are the dark arts in electricity. Buy new……….

Exactly, the cheaper they make the stuff, the harder it is to fix!

Thank you all for your responses.  A new string was purchased, the tree stripped bare, and lights were replaced and tree redecorated.  If the original string had been incandescent I would have never bothered asking.  I didn't know if LEDs suffered from the same issues as the incandescent strings or if there was something simple like the batteries were in wrong.