2xAA battery holder ... In series so = 3v I have alligator clips on mine ...
MM = Multi meter , put the battery in the light , place the neg probe to the back of the battery and + probe the clean threads to close the circuit , check Amp reading , + by tapping the + probe you can change modes .. [ If it wont change modes or your getting high Amp reading ]
Short = Unscrew reflector - check Amps / If no fix - resolder leads to emitter and keep bare wire to minimum [ may short against base ] / still no fix , unsolder driver from pill and check solder work , check to see if anything might short against the side of the pill ...
The driver :
This driver is nuts , Ive left it stock ...
Starts Low - Med - High [ No PWM to worry about ] no mem in stock form ..
Then goes strobe [fast], strobe [slow] , SOS , and Beacon ..
Here is where it gets trick :
If you change modes slowly , it only goes L-M-H , and bye passes the blinky stuff ..
If you want to get into the blinky stuff >
Then you need to change modes quickly , cycle through L-M-H once > continue to change modes so that you do L-M-H again .... NOW !
The second time around lets you get to the blinky stuff , so the 4th mode is Strobe Fast - 5th mode is Strobe Slow - 6th mode is SOS - 7th mode is Beacon
So you have to cycle through the modes and the 2nd time around you get to access the blinky modes = OK ?
Current draw High / 2.28A - Med / 0.72A - Low / 6mA from the looks of it ... [ Thats insane ] It will run for ever on low ...