BLF A6 FET+7135 Light Troubleshooting and Mod thread

My post #199:

Or try the solder blob/paper clip method.

Penetrating oil, rubber, cardboard and pliers did it. Needed rubber again for the driver retaining ring. No sign of problems. Just wired the springs and added heat sink compound around the driver.

Wow, I’ll sure take you up on that offer. PM coming your way.

FWIW, I tried legoing the anodized and bare versions today. The bare ones were recent, of course, and the anodized ones were from the very first batch.

Everything lego’d fine except the bezels. The bare bezel didn’t work on an anodized head, because the bare threads were too big in diameter and slipped easily over the anodized pill without any need to twist or screw it together. The anodized bezel worked on a bare head though.

At least this much works:

Nice TK! I didn’t try the bezel. Interesting look huh?

I didn’t get my A6 head replacement today, was hoping I’d come home from work to find it but mailman didn’t even deliver it along with my junk mail…

Ok, so I went ahead in the quest for troubleshooting. Clickie as said is trashed, but I checked function by manually linking battery negative to flashlight body.

Now this is weird:
Modes seem to change in succession, but after highest setting, instead of cycling back from lowest, it emits a single flick and turns off.

It also whines on the higher modes.

In my opinion, the vendors should find out how to mail something as “junk mail” that way it would ALWAYS get through…. E-packet or J-packet… Nuts on your non-delivery, perhaps your Saturday postal carrier will give you a surprise…

@ chenko. Yes alot of ours do that. I think tk and pilotdog were discussing how they deal with it. But yours has no moon right? So your getting the flash and then off.

Chenko, seems like it’s the 7135 chip causing that issue. Try touching your soldering iron to each of the legs and getting a better solder joint on the chip… that should clear up the issue.

The whining could also be coming from the chip being cold soldered. If you could place the entire driver on a hot plate (after removing the spring) and re-flow the whole thing at once your issues should be solved. Seems like they’re using a high temp solder paste and then not getting the re-flow hot enough to get good liquid connections.

Exactly, no real moonlight mode. And yes again, it flashes and shuts off. So it is aaaa diffused issue? :frowning:

While waiting for the supposedly coming replacement head, curiosity got the better of me when I read about the difficulty in taking off the head. So I opened the head without any trouble. That is good news. The problem was that in opening the head, the led “spacer” dropped off and in subsequent closing the head, it de-domed the led. So I put together again without the dome and found out the real trouble. There is no light, not even the few modes I had before the head opening. No light when connecting battery negative to body with paper clip. Everything is tight, even the two retaining rings in tail cap and head. What’s the next troubleshoot step?

Try connecting a CR123 or a lithium ion cell with long leads to the + and - points on the star. The bond wires may have come off with the dome.

Must be the bond wires as that’s the only thing that could have gone wrong when the led “locator” made contact in “locating” the led. Thanks.

You could check resistance right on the star. If you make polarity right you should get a little light from the led. If nothing happens you may need to reflow it.

After the dome is off, the bond wires are extremely easy to break. They basically should not be touched at all, ever, or there is a large risk of breaking them. They’re hair-thin and made of soft metal.

Chances are that’s what happened, and it won’t work again without a new LED.

Finally got my new head today, most noticeable difference is the longer contact spring. So as usual did a wash down of the light with new head installed, for some reason before fully submerging it (standard personal water proof test) I took a look inside the reflector and there was water in it. Immediately took it out and dried it. Glass was fogging up already.

So yeah, learned how to open the head, tape on head and body, lay it real thick and nice then use hand powwah!...Left light on turbo to dry out the inner parts with the reflector off.

I tried seating the O-ring in front of the glass, however when I tighten the head the oring gets forced out as there is no groove holding the O-ring under pressure, just a flat shelf.

In the end I just applied some superlube to the lens shelf, oring and the portion of the reflector where the o-ring sits on. Seems pretty watertight for now but I do not recommend submerging for prolonged periods.

Despite above issues, this is still my favourite EDC currently and my brightest single cell light so far. Needless to say it gets the ooohs and ahhhs from the uninitiated around here

Lucky you!

The reflector is needed to press the ledboard against the body, which gives essential heatsinking. With the reflector removed the board is not pressed down any more and can come loose. With the light on Turbo in this situation there is a significant chance the board will overheat and the led will fry. This has not happened in your light luckily :-)

Wow it didn't occur to me at all as the LED board appears pretty solidly and accurately fixed to the pill though...I can even see traces of some sort of thermal compound under the cut sections of the board. In fact, I tried wiggling the board with tweezers and it didn't move one bit.

@xzel87,

I am surprised you did not damage the led bond wires with all your tinkering with the reflector. The reflector hole at bottom holds a small plastic piece that “centers” the led. That’s liable to damage the led bond wires by the rotation of reflector when you screw in the head.

[edit]
See the TK’s post above.