Over the last couple of weeks, my beloved Salvo 21W began to misbehave. It would strike, stay on for a few minutes, and then fail. The first time it happened, I thought perhaps I had picked up an uncharged battery. The second time, I thought maybe I had a bad battery.
What I eventually learned is that blinking on and off in this way is one of the failure modes of HID bulbs. I swapped out the bulb, and not only is the light working perfectly, but it is MUCH brighter than it has been for a long time. Clearly the bulb was not working properly for a while.
Anyway, I thought I would share this here, as a lot of people are using HID lights and may encounter this failure mode, and I found it quite counterintuitive that a blinking light was a bulb failure. One difference between incandescent and HID bulbs, apparently!