Help!! Need input: Diagnosing and repairing failed LEDs

All,

I'm looking for advice on how to diagnose and repair a failed LED.

I have a pair of Chinese LEDs, from Reef Radiance but no different than other varieties on eBay, and this week I lost the actinic channel on one of the fixtures. I've been able to troubleshoot down to the actual LEDs by swapping components and here's where I need input:

Typically, are the LEDs wired in series so a failure takes out the channel? My assumption is either a failed connection, possible although the lights are never moved, or a failed diode which seems much more likely.

I do have a digital multi-meter which I could use to test, but if they're in series what's the harm in using a jumper over each LED to test and when the failed one is found the lights should come on?

When I find the failed LED, is there a danger in using a jumper to bypass it? I realize, if they are in series, this changes the electrical load slightly but with 22 LEDs it wouldn't be much variance. As I'm planning on breaking the tank down in the next week or so I'm looking for options.

Thoughts?

I look forward to your feedback!

-Eric

 

Thanks Sponge! Great weather for my birthday - spent time outside and went on a bike ride with the family - amazing for February!

I forgot to post again on this :

Removing the lenses it was easy to see damaged diodes and I confirmed with a multi-meter - when its set to diode a good LED will light up and obviously the bad ones won't. I ordered a replacement set of diodes from eBay for $12 shipped (22 LEDs, various colors) but haven't made time to install them yet.

I ran the blue channel @ 100% to give a 20k look with the white channel @ around 30% which would explain the failure as I'm sure there are better quality LEDs available.

-Eric

 

Example of obvious failure.