Repair Stories

Christmas Lights repair - by Mike H.

Christmas Lights. Well its getting close to that time of year again, Halloween has almost gone and the Christmas things have already started to appear in the shops !. You may have had LED light strings up outside last year and they looked great, they were packed away probably still working but now you've got them down in preparation and you find some frustratingly don't work, some of the LEDs are dark. A common problem especially with the budget brands.

LEDs - suffer from their connection legs rotting away during storage, they get wet whilst they are up doing a great job of decoration. They get taken down and packed away but the damp is still there, eating away at the legs during the year (photos 2&3). When LEDs first commonly appeared some years ago to replace incandescent lamps, they were made on maleable substrates but were expensive, modern ones are now made from tin or copper plated steel, so once stored the damp eats away at the steel, disconnecting the LED, leaving one - or more - not working when you get them out again.

These - are repairable and we can do this for you at the Rushmoor Repair Cafe.
The problem is finding the faulty LED as the faulty one could take out up to 10 or 12 LEDs in a string depending on the connection system as there are several ways of wiring a LED string. Photo 1 shows four LEDs from a partially working set of an all white LED set. The top left and Bottom right are clear, the other two, if you look closely, have a reddish brown colouration to them, this is the rust on the legs, they may still be working but the rot has started. Photos 2&3 show the rusted LED legs which has also crept up inside the LED and got to the housing inside Photo 3.

1) Suspect faulty LEDs.
The middle one is faulty.

2) Faulty LED with rotted leads.

3) Rot is creeping into the LED housing ➔

4) Fixed it but we
don't have a turquoise LED.

All is not lost - these are repairable, the faulty LED can be cut out and a new or recovered one soldered in. The original insulating spacer is replaced, a new clear heat shrink covering is cut to length over the LED and filled with a chunk of hot melt glue stick. When the repaired unit is heat treated so the the covering shrinks, the glue melts and squeezes hot melt around the LED legs completing the insulation and fully waterproofing the assembly. It might sound time consuming but in reality each LED takes just a couple of minutes to replace. Photo 4 shows the replaced LED, in this instance a blue one as turquoise LEDs are a bit harder to source, however the usual Red, Green, Blue, Orange and Yellow LEDs can all be replaced in this way.

To prelong - their life and help to keep your LED lights from rotting - when you take them down and put them back in the box, place it, with the lid open, in a warm place for a week or so (longer is better), on top of a radiator, in the airing cupboard, beside the boiler, just warm not hot, the damp will dissipate. Then keep them in a damp free space.

One safety tip - Never install your outside LED illuminations with the power block or mains plug directly in the open. Place them inside or under dry cover, never exposed or in the wet, you will compromise the installation and risk electric shock to yourself, pets or the public.

Please note - this repair is for the common lower cost LED strings consisting of wired loops of individual single or multi-colour LEDs. LED strings of moulded lights don't or should not suffer from the phenomenon of "rotting" LEDS, repair of these is in general more difficult or not possible.[Back to the top]

Close window - Christmas Lights.