Here's another wrinkle in the turn signals not working drama:

After reading this thread, I thought I'd check to see if my right front turn signal was working OK; it was not, but all other lights checked OK (the original owner replaced ALL bulbs with early LEDs so the CANBUS light out warning light is always on).
So, I pull the socket and find no LED attached!! But the light had been working previously!!!
YUP, the LED is lying INSIDE the lamp housing.
Fishing the loose LED out the housing with a pair of needle-nosed pliars was a couple hours spent while recalling the "saltier" expressions of my seafaring days.
Now the cause of the loose LED and a warning for y'all:
ALL Y21W BULB REPLACEMENTS ARE NOT THE SAME!
The turn signal socket is configured to take a BAU bayonet bulb with a 150 degree pin offset.
The LED that fell out was a BA bayonet bulb with a 180 degree pin offset. What a difference 30 degrees makes!
Whoever installed that LED filed one of the pins off to make it fit, sort of...
But after years of driving the improperly fit LED vibrated loose and fell into the lamp housing.

My right front turn signal not working mystery SOLVED.

Any bets on my other Y21W LEDs?

BEWARE OF Y21W BAYONET BULBS/LEDS WITH BA 180 DEGREE PIN OFFSETS!