This summer when out driving, I've been noticing more and more partial failures of LED traffic lights. It's always the green signal - the failures seem to range from a few "knockout" failures of the green LEDs where a half dozen LEDs on the signal are dead or so, to weird failures where an entire "pie slice" chunk of the signal has gone dark.
Some of the failed LEDs will also blink at about 5-10 Hz or so on and off, or even an entire section will flicker.
I've now seen this on at least 8 different traffic signals within a 10 mile radius. Always the green - never seen it with the red or yellow lights.
What's going on here? I'm in the Boston, Massachusetts area, if for some reason that's required information...