BLF A6 FET+7135 Light Troubleshooting and Mod thread

All right, I understand. I will buy it and install it and report back on the outcome. Thank you for your help!

New switch arrived today and it was installed. My light now works properly again! Thank you g_sintornillos!

Hi, hoping someone can help.

My A6 is immediately going into low voltage protection mode with a fully charged battery. I’ve tried a couple of Quality batteries (LGChem, Samsung Q30, Panasonic) and they are all the same, so i’ve ruled out a bad battery. I’ve also double checked the voltage of the batteries with a multi-meter and they are ~4.1v so near enough fully charged.
Tried removing the tail cap and directly shorting battery to the tube to turn it on. Still does it so it’s not the tail cap.
I considered replacing the driver, but can’t work out how to get the LED board out (is it call the STAR?)

It seems like a great flashlight and it was for about 2 weeks before it started shutting down constantly.

Any suggestions on how to solve the issue or how to disassemble the light?
Don’t want to throw out a near new flashlight :frowning:

The only thing I can suggest is to make sure the driver retaining ring is tight, the spring in the head is not oxidized, and the body tube end is clean. But you’ve probably tried all that. Other than that, I can only think it’s something in the electronics. Unscrew the retaining ring and take out the driver and replace it?

It is a great budget light. My only complaint about it, which is the same complaint for almost every budget light, is that it is not regulated and dims as the battery voltage goes down. For me, that means that most FET-driven lights are really only good for the top 50% of a battery charge, essentially cutting my battery’s useful capacity in half.

But for $20 or $25, what can you expect? Personally, I’d just buy a new BLF A6 to replace it, but if you’re comfortable messing around with it, replacing the driver is a good bet to try.

It sounds like there’s some large source of resistance somewhere in the head end of the light, or between the head and the tube. As suggested, try cleaning and loosening/tightening everything.

On a different note, the first three modes don’t use the FET at all, so they don’t dim until the battery is almost empty. Anything over ~140 lm uses the FET though, at least partially, and will change brightness with battery voltage. Mode 4/7 only uses the FET a little, so it doesn’t dim very much. This means four of the seven modes keep pretty consistent brightness, and only the top three are really prone to sagging.

Thanks for the suggestions. I have done the “spring bypass” mod to try to improve/reduce resistance where i could. Initially I thought it had fixed it but the victory was short lived.
I’ll take it apart again and confirm the connections are firm.

It definitely steps down through the modes right down to Moon mode.

Update: relocated to its own topic thread: Morse code paddle integration with BLF A6 FET+7135

Okay I’ll start by saying I have ordered this flashlight blf A6 but I’m still waiting for it to come in so I don’t have hands on experience yet. I also ordered the USB interface so I can reprogram it if necessary.

What I’m trying to do is interface it with my Morse code paddle. A morse code paddle is basically a fast way to type Morse code. I’ll try to attach pictures; but long story short there’s two paddles, hold one down and it goes dit-dit-dit hold the other down and it goes da da da hold them both at the same time and it goes dit da dit da dit da ( dit = the shorter or . sound and da = the longer sound or - ) when it alternates it starts with whatever paddle you touched first. If that doesn’t make sense and easier way to say it is there’s two levers and with just two movements you can type any letter. I built this myself I’m not an electronic genius or anything I followed YouTube blindly soldering together what I was told and lo and behold it works. I also had help from Friends.

You’ll see a schematic below basically the paddles make a buzzer beep the morse code out there’s also a connection for headphones which is labeled external speaker and there is also a mosfet it is labeled U2 BS170 there is an auxiliary cable just like a headphone connected to that mosfet there is a picture I’ll attach that shows what it out puts on the cable for when it is keyed and when it isn’t that is making sound and not making sound.

What I’m hoping to do here is make the flashlight flash the code as I type it this is going to be sort of a niche novelty thing not every day so I really don’t want to majorly modify the flashlight or the paddle as it’s normally used connected to my radio for international coms.

What I’m wondering is can I connect the output cable from the mosfet to the driver and it just work that way or do I need to come up with something more complicated like figuring out how to connect the pic leg that drives the mosfet on the paddle directly to the mosfet on the board? I have a magnetic connector ordered I’m hoping to put it on the side of the head of the flashlight and use it to connect whatever wire I have to use so I don’t compromise the waterproofness. I can send more pictures if anything would help let me know and if anyone knows who would be able to help me with the driver interface here please tag them or let them know this is my first post so I really don’t know anyone. I want to thank you all for your help just by existing and sharing your knowledge led me to this moddable driver and the tutorial on how to flash it and that’s why I chose this light and this forum for this project.

Thanks for any help.
Rowe

PS if there are major modifications necessary to the paddles I can build a second board and dedicate it to the flashlight exclusively but it was kind of expensive mostly in shipping of everything so I would rather have something reversible or preferably just using the mosfet driven output switch that is already connected to the auxiliary cable.

Hi all.
I successfully build and flashed two different blf-a6.hex files on my modded c8 and on my triple s2+ to change the turbo timers, but I have an issue.
The medium and the long press require pressing the switch for much more time compared to what it should (0.5s-1.5s and >1.5s respectively). On stock firmware it works fine.
I also flashed the latest blf-a6.hex from the ToyKeeper’s repo and it works fine.
I suspect that it has to do with the off time capacitor values in tk-calibration.h file.
The thing is that I don’t know what values to use.
The drivers are the banggood a6 ones.
Any help will be appreciated. Regards.

gismo, you may want to use the blf-a6 code branch instead of trunk. I think it has the values calibrated to match banggood’s drivers. Or use the values in battcheck/readings/manker-a6.*. Or measure them yourself using the other tools in the battcheck/ directory. The process is explained in the README file there.

ToyKeeper, the code from blf-a6-final branch did the job.
Thank you for your prompt response and for your contribution to the budget light community! :+1:

A couple months back I received a BLF A17DD-L driver that would misbehave.
Basically even though I would trigger a mode change, the output always stayed at the lowest level.

Today after a brief inspection, I found out that it's missing the R1 22K resistor - probably a factory defect.
I read that the resistor is part of the voltage divider.
Since I don't have the exact same Ω rated SMD resistor in hand, could I replace it with a different valued one?
What's the Ω range that I should shoot for?

Pic for refference

If you change the resistor value, it’ll mess with other things too… and you’ll have to recalibrate and reflash the firmware, assuming it even works at all.

The calibration process is documented in the ToyKeeper/battcheck/ directory.

Thanks for the answer ToyKeeper. Your readme describes thoroughly the whole procedure.
As you might have already guessed, I won’t be going through the hassle :slight_smile:

Hi all!

I damaged the LED so I need to replace it. I have the 1A version (cold). Can someone please tell me where I can find a replacement? What exactly do I need? If it is possible to replace the whole head… even better. So I can spare myself of soldering. I can’t find any parts on the web :(.

Thank you!

Grab a Noctigon MCPCB with an XP-L or XM-L2 emitter already installed, probably from somewhere like intl-outdoor.com, and it should be pretty easy to replace the emitter and the board it’s soldered onto. Just get one matching the original MCPCB size, and it should work fine. This will require unsoldering the +/- contacts though, then soldering those wires onto a new board.

BTW, if you want it more throwy, try XP-L HI.

My favorite for this light is XP-L 3D or XM-L2 3D. They give a nice wide hotspot in a neutral tint. I don’t recall offhand which one fits the centering ring better though.

MCPCB CREE XP-L V6 1A LED on Noctigon 16mm MCPCB
Thermal compound under the MCPCB Search - compound
As your from greece this may not be a good shipping option but this is what you’ll need for the swap.
16mm copper board with led and thermal compound to transfer the heat to the flashlight.
Fasttech, or Kaidomain, may be cheaper on you from your location.
The swap will require soldering as Toykeeper explained. Not very high on the difficulty scale.

Thank you both for your suggestions!

Hey guys, I need an other advice. It is not possible to unscrew the head of the lamp. And I mean, I cannot unscrew the tube that contains the driver & the LED from the tube that contains the reflector. Anyone who had similar issues? Any suggestions? I don’t want to damage the tubes, thus I did’t use any tools, but for sure I tried very hard, it’s just not possible. Thank you!

If you have a pair of rubber gloves lying around, that might give you a bit of extra grip. Otherwise, you could try a pair of strap wrenches, although you might be just as well buying a new light for the cost of the strap wrenches and the spare parts.

Rubber gloves made the job! That was I great idea! Thanks a lot Phlogiston! Cheers!