Beware of that front battery at .00Volts CK for a Short from battery case battery Tube.
I haven’t got a clue of how that happened but I assure you that the light was tested before and after the mods.
After a minute it did get hot and I’m guessing that the solder could have reflowed and bridged.
lawenforcementguy, are the batteries protected or unprotected? If the one showing 0.0V is protected battery then maybe it is just the protection circuit failed, or need to be reset; But if it is unprotected battery then I’m afraid 0.0V means the battery is gone.
Chazzy, wow you have boosted it to 3.6A! that’s too high for this driver and I guess this is exactly what causes this to happen? My stock driver already failed at 2.20A measured at tail (only one extra R100 was addded).
Yeah they were unprotected, but for sure the next ones will be protected! Taught me a lesson for sure. Chazzy, no worries I knew it was a gamble anytime to buy modified stuff I sure ain’t blaming you. I am looking forward to doing the new driver myself and learning more.
Since you want to keep it running with two batteries I think LD-4B is the only choice at the moment. If you don’t stack resistor on the LD-4B the output current is about 2.2-2.4A to the LED (particularly from IOS). If you use dedomed XP-G2 you will still see fairly good throw running it at 2.4A, probably around 250kcd and you have the good High-Med-Lo modes.
And again stacking resistors on the LD-4B is not advisable. We just got to be a bit conservative with this driver for better reliability especially you will use it on your duty.
I have tried to fix the Driver
as long as i do big numbers of laptop pulls and i was keeping those battery circuit boards for something like that
i have tried 3 components that have the same shape of the fried one on my driver
the 1st one worked but i was getting only one mod and it was very low
the second one gave me the whole five mods but the high mod was only 600ma
With the third one i have decided to replace the working component on the left to replace the damaged one on the right, and used the new one from the battery circuit on the left just in case and then hooolaaaa the driver back in line and working as nothing happened to it H)
ofc i was just lucky iam not an electronics expert or anything it is just luck 8)
Any way I have Fixed the driver 
You're a true component magician!, who knows how many types components come in that package?.... and you found one that does the job!
Great modding!
Well I got the LD-4B driver for mine and put it in the De-domed one.
This pic doesnt do it justice, its noticeably brighter in the circle then the stock one.
LD-4b on right dedomed, stock 1405 on left.
Cant wait to test the throw out tonight at work when im doing the perimeter security. Thanks for the heads on up on this driver.
Nice. What LED are you using now?
hi, could you suggest me a new driver to mod my unit? i would push higher amps and lumens from the original xm-l2 led.
but… i only find driver that does require 1lithium battery. i need one that can push over 4amps and accept 2s battery configuration
AFAIK there is no any good 17mm buck driver that can handle high current (>4A) at the moment.
I use the LD-4B in my 1405 with an added R120, I did not measure the output current but I got 2.4A at tail. Its light output is good but I personally won’t recommend anyone to go high current with this LD-4B because high current is really pushing its limit. After the resistor-mod the driver mode changing behaves strangely and and the light cannot be operated for more than 3 minutes on high mode otherwise the driver will be overheated. In short it is not really a good setup but I can’t find anything else better right now.
The focal length looks very short from the pictures, I thought longer focal lengths are better for throw. Anyone knows what is the focal length of the lens?
I’ve never measured the focal length of it, but focal length has nothing to do with throw. The lens diameter is what matters.
I found on this spanish speaking thread that the difference in length between flood and zoom is 2.5cm, so I assume the focal length must be around 25mm.
Diameter definitely plays a role but I thought that the focal length affects the divergence angle which would affect throw.
No, the focal length will not influence the throw at all. The difference in focal length only determines the amount of lumens loss.
Let’s assume there are two pieces of aspherical lens, both having the same diameter (say 50mm), same build quality but come with different focal length:
The one with shorter focal length will ‘collect’ more light emitted from the LED, hence lower lumens loss and the projected die shape will be bigger;
The one with longer focal length will ‘collect’ less light emitted from the LED, therefore higher lumens loss and the projected die shape will be smaller.
But if you measure the candela (throw) of both cases they will be the same.
The idea of pre-collimation lens is also the same.
You are right about the example. The only way to benefit from a longer focal length is to also increase the lens diameter so that you are collecting the same amount of light but with a reduced projected die shape which would give more throw. I never heard about pre-collimation lenses, is there a good website with more information that you would recommend reading?
Hmm… I can’t think of any good source to read about the collimation things at the moment. My very limited knowledge was gained from reading different threads and discussions here in BLF and playing around with different sizes of lens.
This thread has some photos and illustrations constructed by the OP. Maybe you can visualize something from there?
Dr. Jones’s thread is less related to your question but more about the dedome phenomenon. Anyway it is still a good read though. It is very informative.
Maybe other members can chime in and help. 
Hi friend,
I will give an example of different 50mm lenses (left tablo A9 right Dereelight Nightmaster) and my observations on them:
- They both have same die projection, but left lenses has cleaner die image
- Right lenses have about 15% more throw but they also have much less flood when zoomed out than left lens
Left lenses: clear die projection, and very good flood mode
Right lenses: fuzzier die projection but more throw, and very weak flood mode
Mystery to solve why left lenses have less throw than Right one?
Same thing happens with goread a2 50mm lenses which are even lower profile than left(tiablo) lenses on picture, and goread lenses give excellent die projection, even better flood mode but still much less throw then right lenses on picture, and now less throw than left(tiablo)lenses.
So conclusion here from my redneck testing method(all lenses tested in same host but I had to use different distances from emitter) is that lenses with lower profile, or lower height will have less throw but clearer die projection and the better flood mode than the one with longer profile.
Dereelight lenses beat all mention lenses of same diameter but with terrible flood mode comparing to other ones.
I want to say Bibihang that candela difference of right lenses is 15% more throw on left(tiablo) lenses and 25% more throw on goread a2 lenses(short profile 50mm lens) so candela difference is very visible and they don't have same measurements as they supposed to have by your theory 
Bibihang's explanation is not a theory, it is an explanation that need not to be proven, it is simple high school optics. (thanks btw, usually it is me who has to do that explanation ;-) )
That said, the simple lens theories do not include lens quality, it assumes perfect lenses. So if you find throw differences between lenses, it may also be a quality issue. Luminarium ejaculator has done testing on that.
When I hear name Djozz it immediate associate me to BLF. Djozz is BLF.
To continue testing... Forgot to say that right lenses can be put at shorter distance from emitter for best focus while left lenses need spacer and of course larger distance from emitter, and Goread a2 lenses needs 2 spacers and greater distance from emitter to achieve best focus.