Fix Led Bulb

I was disappointed with low life duration of a led bulb . Less than 1year is a shame , so i decided to make some research and found out that those bulbs have a circuit inside of it with many led in series . Like blinker christmas lights if one is burnt all the other don`t work .

1. Notice that there are many reasons to bulb not work .
2. Only fix in this instructable is led damaged .Also notice this is a quick fix.
3. Right thing to do would be replace burnt led .
4. I know that Ohm law should be considered and used a resistor

Step 1: Opening Bulb

Those bulbs are easily opened using a screwdriver around the joint , pieces are made of some kind of plastic , so no worry about break things .

Step 2: Testing Leds

Leds are diodes that emit light , then being a diode means that current goes just in one direction , not the opposite . Using a multimeter to make a continuity testing (shown in picture). Test all of them , when find the one that don`t turn on make some mark on it with a pen.

Step 3: Smash the Black Sheep

Smash burnt led with flat nose plier . It is easy

Step 4: Soldering

Remaining place left by led are metal base on PCB . Use solder wire and soldering iron to joint separated metal base.Glue used on bulb is not strong ,i just closed bulb attaching spots on there , but if necessary can be used some glue to make it stay closed .

Step 5: Finish

As led are very bright i could not show the result , i mean other leds working despite that there is one less. I am very happy with result , my led bulb working again. As there was another bulb left a did the same process and got another bulb back to life .

Comments

[dwayne6]

won't this method burn other led because of over voltage due to one led removed in a series? in that way is this safe to use.

[YigitElectroMan]

LEDs contain toxic chemicals and other harmful substances
DO NOT smash an LED like this article tells you to do

[themactep]

California much?

[rootol]

Hi,
Any of the diodes in my lamp doesn't turn on. Why is that?

[E_Alves]

Do you mean using multimeter and leds are not working ? I dont believe all of them are damaged . Remember that diodes let current go just in one direction .

[rootol]

I checked both direction and it didn't work. So I verified another separate diode I had and it was ok which proves multimeter isn't the reason. Anyway, I googled and found that I can find failed diode visually - it will have small black dot in the center. I found one and give it a try. I removed it, re-sold and guess what - bulb was fixed ;).

[E_Alves]

Glad to hear you got it working . I have done this trick in 2 bulb almost a year an it is still working .

[NickSango]

Can someone please clarify the soldering step? Do I just put a bead of solder over the smashed LED?

[E_Alves]

Yes , just make contatcts close , it make electricity flow again.

[NickSango]

I tried it, but it made the light completely die (it used to have some leds working). Any idea how to fix what I made worse?

[E_Alves]

Do you mean it was working before ? Also keep in mind that there are other reasons to bulb not working , and i suppose there is a limit for this trick(with soldering) work .

[NickSango]

Half of the light worked before. When I touched the soldering iron to the broken chip the entire light worked. However, when I added the solder the light stopped working. The light I'm working on is a flat grow light, not a bulb style like this article was written for...
I think I just realized it's because the diffuser panel surrounding the chip is actually metal. However, when I removed the solder it still doesn't work. Could I have fried something?

[E_Alves]

Check if you have removed entire solder. But know that if the leds are connected in series (not parallel) voltage is divided to quantity of elements and amperage is the same on all elements (Parallel is the opposite : voltage is the same and ampers is divided ) , this said ,removing one element voltage goes a little bit higher on remaining elements , i suppose leds lifespan is shortened if soldering work (but work) ,if not work or work for few time could mean that higher voltage on leds were to much and some of them get damaged. Check others leds again .

[NickSango]

Thanks!

[grasnall]

And what will happen if you have two or more defective leds ? Would it not be the case of changing faulty leds ?

[E_Alves]

As i mentioned above ,on introduction, right thing to do is to replace damaged led . And as MikB replied my comment below ,there are some possible situations that could influence current limitations , voltage , etc ; but this is another target , not target of this instructable (easy fix) .

[E_Alves]

Hey

If by how often you mean how many leds can be done this trick , well, blinker christmas lights(regular lamp) have a specific number of lamps to match the rule (in a serie circuit voltage is divided by the number of lamps , amperage is the same ) . In our case one led is suppressed, then theoretically other leds have a little bit more voltage (i guess input voltage on leds are 9V) , if so instead 0,321428571V (9\28) there is 0,333333333V (9/27) . LED max voltage input could be the limit , but i have no experience earlier.

P.S. (Solda Cobix :) . Brasileiro ?)

[MikB]

Ordinary (incandescent) bulb Xmas lights will tolerate this trick, up to a point -- in fact some of them have bulbs which will self-short-out when they fail. True, each other bulb will see a higher voltage, and eventually this will lead to a cascade failure. So you should replace them as soon as possible.

But for LED strings -- if there is a current limiting circuit (not just a resistor), then removing and shorting one or two LEDs like this will make no real difference. The current limiter will still allow the correct current to flow, and the voltage dropped across each LED will be the same. The difference will be the voltage dropped across the current limiter circuit.

[ManoelG3]

Nice I'ble, the photos are very good!
In your experience, how often can a failed led lamp be fixed this way?
All the broken lamps that I've examined so far (I had disassembled many of those which I can put my hands on), had failed in the electrical circuit, not in the leds.

(tá usando solda marca Cobix? ;-)