Sounds like maybe the 7135 chip died, which would also cause the battery check mode and config mode to not look like they work. The amc7135 chips don’t respond well to excess voltage, even if other components survive.
I see. how do AMC7135 chips usually die? Aside from over-voltage? How about over-current? or other scenarios?
Usually just from excess voltage, which makes them overheat and burn out. Afterward they usually stop responding to the MCU and let a constant amount of current leak through. This would make all the 7135-only blinky modes stop blinking, and would make moon and other 7135-only levels all look the same.
Anybody know where I can get a new reflector? I had a little accident with mine 
I’m currently using a smooth S2+ one but it doesn’t have a groove for the oring.
I’ve killed more with excess heat [during soldering] than any other way.
I ONLY reflow 7135’s now, not that you can’t still overheat them but I find I have a whole heck of a lot lower failure rate with hot air then I ever did with an iron.
Is there a way to test the 7135 is ok, say with a multimeter? I suspect mine may have also gone as it appears to be stuck in the highest 4 brightest modes and I can’t cycle to the config menu.
You didn’t try to put a lighted tail cap in it did you? I know that will cause that problem if a bleeder resistor isn’t used when installing the lighted cap.
Nope, everything as standard. I believe the lighted tailcap issue is that mode memory won’t work correctly, i.e. mode memory will be on even if set to off.
I see. I think this thread is what you are looking for.
Thanks, I’ll take a look.
Are there holes in the UI? In lower modes the FET isn’t on at all so if the 7135 has gone bad there will be modes (moon & lower modes) where there’s zero light output. If that’s not the case it’s probably not the 7135 being bad…
Anuway to test the 7135 you jumper the right pin to Vcc, this will make the 7135 turn in full (0.35A) which you can measure to confirm its good.
If I recall correctly, the 7135 chip tends to fail in a way which passes current, so it would have the same brightness regardless of the PWM signal sent to it. If the lowest few modes are all the same, that may be what happened.
No holes in the UI. Essentially the light has 4 modes consisting of the brightest 4 modes of the 7 mode group (compared against my other A6).
Thanks for the info on testing the 7135, I’ll take a look when I’m back home.
Would a failed 7135 prevent access to the config menu?
There must be multiple failure modes possible then cause I’ve had more than my share of them suffer heat related deaths in which they have zero output. The only time I’ve had them fail in a way which causes them to stick open is in over voltage scenarios (2s builds).
My experiences have been what TK mentioned - they fail for me wide open. I've killed several this way on my modded 35K lumens XHP50 based light, and in a couple triple XHP70's I modded, all with FET+1 drivers. Ohh yes, same thing CK is saying - all in high powered 2S builds.
it is possible to adjust current in firmware of a6 driver? i want to get about 4,5A-5A in fet turbo mode
Well no, not exactly. Firmware has no control over a FET based driver accept for PWM'ing to lower the effective amps, but not to any exact amperage level - it can't read back amps, can't adjust accordingly. You could add resistance (thinner, longer LED wires for example), but that depends on the cell also.
Hi everyone, my first post here, my first flashlight which was recommended to me.
I just got it in the mail, but have the following issues:
I press the button (click), and nothing happens (this is where moonlight should be). A half-click gets me to a low setting, the next half-click to the exact same setting (definitely identical), and then it gets all the way up to turbo. So basically I’m missing 2 out of the 7 modes (moonlight and low or med1).
In the second group (supposed to be 4 different modes), the first two modes are identical (so it’s 3 instead of 4).
Switching between the groups is possible, but there are no two blinks as there should be, it’s just dark, I can still get it done just by guessing.
Battery check also does not work.
Is this a known problem/easily fixable by a noob, or do I have to send the lamp back?
Thanks in advance for your feedback!
It sounds like a hardware problem, like the driver has a bad amc7135 chip. It’s not easily fixed unless you have some of those hanging around and know how to resolder it.
Thank you so much for your reply! :+1: Too bad that the first flashlight I order from China has this, but I’ll see what the vendor will say!
I really have no experience in the field whatsoever, naively thinking there might be something like a “factory reset” to fix this! I guess I’ll just have to wait for a few more weeks then.