When one fails they will all start to fail. It is over my pay grade to understand but so I have read. That is a problem with the LED units themselves. I would contact vetteronics to have it repaired. he said he stands behind his work.
the best is to replace ALL other wise you screw your self since you replace burned out one only then you still have the old ones..
I bet he buys sylvania LED bulbs(the ones you buy at auto part store) and the strips the parts from the off the shelf LEDS (better then the cheap junk on ebay)
sylvania LEDS are high quality leds
It's actually not hard to solder
and replace them your self for pennies on the dollar (compared to paying someone)
this is surface mount which is easy I think it can be done for about 150 to 175 (the welder iron is the most expensive though) about 125 for a good one (DON"T use cheap 5$ mains input one those will damage the PCB in the tail light since it's a single layer printed circuit board)
a good temperature controlled one will be will do the job good
All the internal parts are replacabe but i.e PCB (EASY to Copy ) the issue is the cost for low production plus the risk of getting sued by gm since PCB are copyrighted protected.. But you can do your own PCB it just has to be different ( not very hard to do "single sided work")
and the work is outsourced to china for the PCB that is the way around it
