Flickering is the current jumping around. That could be from several different things. Maybe a bad connection, a very tiny short between components some where, or a bad or shorted capacitor. If the flicker seems like it’s a constant timed thing like ever 2 seconds then I would suspect a capacitor being the problem, maybe a small short. Its being charged up then discharged causing a slight burst in current. If it’s erratic flickering then the search for the problem is pretty broad. Take a really high powered magnifying glass and have a look around for anything that shouldn’t be connected or something that may not be connected good. You can also use a DMM to check connections but that’s a little more extensive since you kind of need to know what your looking for in terms of readings and circuit layout.
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Being that the driver has not been modified from its factory condition besides the capacitors you solder back on, that be the first place I would look.
Hope you find the problem, I have had shorts that couldn’t be seen with my tired eyes but under magnification they stuck out like a sore thumb. :+1:
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The Olight 10C battery is a very good 16340 battery, it’s what allows the S1R II to achieve 1000 true lumens, tested it in my lumen tube.