Turn ring to left to loosen.
Anyone play around with the Group 2 - Strobe mode.
I can only go into the strobe mode for 1 time only after i received this light. I cycle from candle > bike flasher > party strobe > tactical strobe > lightning storm > off.
Problem : after that i click, click, hold it just respond by dim flash once and turn off by itself.
reinsert the battery still the same problem. dim flash once and turn off by itself.
Light Arrived but does not work.
Had to leave home and took it with me.
Order with battery, assuming the battery arrived with partial charge. Will try another battery when I get home.
Removed tape from negative side of battery and reinserted.
When screwing on the head the light blinks twice, after first blink there is about a full rotation and it blinks again. At this point it is fully closed with no gap.
Retaining ring seems to be in place, will not budge with pliers either direction.
Tail cap is screwed tight no gap. Button click feels good.
Symptoms:
Light doesnât turn on.
Click tail button does nothing.
Hold tail button for 3 or more seconds, light blinks upon release.
Havenât seen these symptoms posted yet. Any ideas? Besides verify battery.
Thanks
@ Phaze13
Try cleaning the threads.
Go HERE . Read it, do what is says again, also look at the driver to make sure it is seated correctly. 
Cleaned threads, nothing to find. Driver seems seated however I canât budge the retaining ring. Certianly not loose.
Still same symptoms, not working. 
âŚâŚ Take the tailcap apart & see it there is a ânubbinâ in it.
If you need it, you can go HERE and find info on tailcap disassembly & ânubbinsâ. :+1:
The nub is there, tail switch feels like its working.
⌠WowâŚ.
The only other thing âIâ can think of isâŚ. take off the head & look at the end of the black inner tube. It should be clean & shiny with no anodization. Give that end a good wipe with a rag, put the head back on & try it.
Guess the low operating voltage of the FW3A is higher than the Emisar D4.
Battery that worked (emitted light) in the D4 didnât work in the FW3A.
The battery ordered with the flashlight (Sony VTC6) didnât come with enough of a charge.
Coincidentally the battery (LG HG2) that was working in the D4 was low enough not to work in the FW3A.
Charged batteries over night, all good now.
Only other batteries I had charged last night were protected cells which as stated donât work.
Thanks for the help.
You had not charged the battery?? 
For future reference⌠batteries do not come charged. They usually arrive around 3.4 V to 3.6V
When my fw3a was working it worked right up to when the lvp kicked in ,it should work with a cell at 3.2-3.4v.
When I put it on the charger it read 3.2 & didnât work.
RFI? Set an AM radio to the noise between stations and walk around your house listening for noise sources, many LED and CFL light bulbs are great producers of Radio Frequency Interference. You may have a âbuzzâ signal from something nearby. And you may also pick up a burst of electronic noise when a flashlight driver operates, if itâs not well designed to avoid creating RFI.
Electronic waves are simiar to ocean waves in that several waves can combine to create a ârogue waveâ or a strong electronic signal spike momentarily.
Iâve noticed fairly often that using a ham or GMRS/FRS âwalkie talkieâ radio triggers various motion sensor lights around the house, and I once had a neighborâs car alarm trigger just as I walked past it while using the radio.
Itâs not just me: ham radio motion sensor trigger - Google Search
https://www.reddit.com/r/amateurradio/comments/7qg9ta/motion_sensing_light_can_seerf/
It might be worth reviewing the FCCâs âshall not cause interference/shall not be overly sensitive to interferenceâ testing for the electronics.
Not surprised it didnât work. But allâs well that ends well. Youâve now got a super clean, checked out, & working FW3A out of the deal.
All for the price of charging the batteryâŚ. 
. :+1:
FWIW, the light should work until the battery gets down to 2.9V or so, because thatâs where LVP activates. It technically should still light up even as low as 2.6V, but itâll shut itself off pretty quickly to avoid hurting the battery.
Brightness gets lower and lower as the voltage drops, in a pattern which should almost exactly match the Vf curve of the emitters being used. Everything used in the FW3A should light up at least a little at 2.9V though.
Phaze13 said his would not work at 3.2 V, any idea why? Just curious⌠??
It wasnât the battery that was causing the problem probably.
Good point. Quite possibly the correct answer. Either the battery was not really at 3.2 V, it was much lower; or during the multiple takedowns he inadvertently âfixedâ whatever was not tight or lined up properly.
The inadvertent fix is my favorite fix.
âHow did you fix it?â
âI took it apart, put it back together, and it worked.â
âGreat!â
Maybe a combination of the battery and the 1x7135 channel chip being bad?
With a depleted battery the light should turn on in low. I assume if the battery is low enough only the 1x7135 channel is activating. If that 7135 chip is not functioning, perhaps you end up with a situation where the light stops working at slightly higher voltage than it should.