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Hello.  I am always wanting to learn, particularly about issues with LED lights so I can learn to sorta diagnose.  Attached is a video of one of the symptoms of the Sixpar’s issue that it is having.  The first symptom it showed was with all LEDs on creating white, half the the LEDs (Green and blue) would flicker and flash on and off, or just stay off. Shortly after, the blue would barely turn on at full, it flickers, then one side would flash on and off as the video shows.  What is causing this??

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It is more likely an individual LED diode rather than a driver going bad. The reason this usually happens is one of the colors in a 6 chip diode dies open, meaning it won't pass current. Each side of the fixture is wired in series.

In the video, when half of the diodes go out, those 9 diodes are wired in series and one is bad (intermittently) and if that happens, it behaves like old Christmas lights and takes out the others. Even though there 9 chips per half, each chip has an individual LED for each color. If the other colors work, it is just one of the smaller color LEDs that died and not the entire chip itself.  

The driver PCB drives both haves at once. If it was the driver you wouldn't have that color at all. If you notice, the working side gets brighter when the other side goes out. That is because the voltage drop from only half the diodes is less though the driver than with them all on, so it drives the working ones a little harder. This can possibly burn out the working diodes faster since they see a higher voltage. 

Out of all of the SixPars I have repaired over the years, I have only replaced one driver PCB. But I have soldered in probably 50 of the "Single LED for SIXPAR" chip you can get from the Elation parts store to repair this exact issue across the 200ish Sixpars the company I work for owns. The trick is finding which exact LED is causing the issue. Its usually only 1. 

If you have decent experience soldering you can replace the individual diodes. These are SMD LED diodes, which are more difficult to solder and require a good temperature controlled soldering station and skill, otherwise, you will burn out the diodes with heat.  

You can track down which LED it is by using a Digital Meter in diode mode and with the fixture unplugged probing every single leg on each of the DIODEs and seeing which don't light and pass voltage.

OR with the fixture on and the intensity set to 20% or something low, you can try bypassing each color of each LED with a short piece of wire until the side comes on full. The one you are jumping when it works again is the bad one.  Make sure the fixture is not on full, because you will give the LEDs in series a higher voltage then they are designed if you have it set to full, and you will blind yourself.

The voltage on the PCB when in operation is about 22v if I remember. Not enough to shock you, but it will let the smoke out if you touch the wrong parts. 

The solder-free option is a new LED PCB. 

Last edited by EvanHopps
@EvanHopps posted:


You can track down which LED it is by using a Digital Meter in diode mode and with the fixture unplugged probing every single leg on each of the DIODEs and seeing which don't light and pass voltage.

OR with the fixture on and the intensity set to 20% or something low, you can try bypassing each color of each LED with a short piece of wire until the side comes on full. The one you are jumping when it works again is the bad one.  Make sure the fixture is not on full, because you will give the LEDs in series a higher voltage then they are designed if you have it set to full, and you will blind yourself.



Thank you so much for this post.  I had been searching for why the Blue channel didn't come on more than a visible dim even when set to full brightness.  Both the Multimeter in Diode mode and the jumper wire method worked to confirm 2 bad LEDs, one on each half. 
I appreciate the clear steps on how to diagnose and will be swapping chips from a donor light soon.

Inconsistent power supply can cause flickering, especially if the green and blue LEDs are acting up. Also, consider checking for loose wiring or connections inside the unit. Sometimes, a simple re-soldering or tightening of connections can fix these kinds of issues. Interestingly, I never realized the importance of proper device maintenance, particularly in terms of charging, until I stumbled upon an article on leds.to. It explained how negligence in care can drastically reduce both the lifetime and functionality of electronic devices.

Last edited by th

@th
In our case, the blue section of individual chips are completely failing.  Testing the individual legs with a Multimeter diode test shows blue (or green) completely dead on a few chip, but working on others, so unfortunately, resoldering the leads won't fix that part.

I am finding it near impossible to desolder the chips with my tools and experience.  Lots of flux and 2 hot-air rework stations on both side of the board and I have only managed to remove 3 without tearing the LED apart and that was after 15-20 minutes of fiddling with each....

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