Welcome to CPF, Brian Ski! :wave:
First I'd check it isn't a bad contact, loose retainer ring or something like that. Final assembly is often shoddy on such lights. :shakehead And check (read:
measure) the function of any switches. For cheap lights, that's usually a single tailswitch.
Normally you can unscrew the front bezel & remove the reflector to get to the LED from the front. This may not be necessary though.
If you can unscrew head from the body tube, you'll find there is some metal ring that holds the driver board onto the 'pill' inside the head. If not soldered in place, you can unscrew that ring, using whatever fits (paperclips may come in handy
).
At that point it should be easy to get the driver board out. Measure its diameter, that's the
size driver board you're looking for. The other thing to watch is the vertical room in that space between driver board & LED. For common drivers using AMC7135 IC's, that's usually okay. But for a high-power driver that uses 1 or more inductors (coils), that height may be a problem.
With the driver board out of the way, you can remove the pill itself (again, may not be needed). Or unsolder a wire to the driver board, and test the LED.
Doesn't look like they make 2 modes...
There's quite a few 2-mode drivers out there afaik. But mostly there's driver boards with more modes, that you can configure in different ways by making or cutting some connections on the board. For example to disable flashy modes (strobe / SOS) or choose between low-high and low-med-high. In some cases it's even
possible to re-program the microcontroller on it. :duh2:
If you decide to disassemble the light, can you make a 'group photo' of the parts?