led tail lights stopped working

[emf]

I tried to search the forum for an answer, but was not successful. I recently put led rear lights on my roadster and have been very pleased with the results. Today, a puzzle...

The tail circuit has stopped working. No lights. These are 6 volt units on positive ground system. Both sides no longer light, but the license plate circuit is still working, so I know power is reaching the lamps through the wire harness. The brake circuit still works. I need to find the schematic for these lights, since it appears from looking through the clear resin that most of the components are resistors and leds. there is one diode. If there was a surge at one time, the lights would have had to be on to blow the diode.

Does anyone know the manufacturer of these lights?

Frank