How to replace Fenix TK35 LED?

The Fenix TK35, which I used well, but LED was died. I want to repair it, but the heat sink does not turn at all. Does anyone know how to fix it? Thanks.

It definitely looks like it's meant to unscrew, so more force or a tool that gives you better purchase on it may be necessary. LEDs are rarely the failure point when a flashlight stops working; are you sure that's what's wrong?

Fenix has a lifetime warranty. If you didn't damage the light through abuse, and you're potentially willing to accept replacement with a newer model, you may want to contact them instead of trying to repair it yourself.

Zak said:

It definitely looks like it's meant to unscrew, so more force or a tool that gives you better purchase on it may be necessary. LEDs are rarely the failure point when a flashlight stops working; are you sure that's what's wrong?

Fenix has a lifetime warranty. If you didn't damage the light through abuse, and you're potentially willing to accept replacement with a newer model, you may want to contact them instead of trying to repair it yourself.

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It is certainly a broken of the LED. It works properly when replaced with a different head, and shows signs of LED failure.

and, there is no Fenix repair center in my country, so I have to repair it myself

Fenix is known for threadlocking their pills. And they use a LOT of threadlocker. I think the red stuff.

Removing it will probably require a blowtorch to loosen the threadlocker... definitely not easy.

You might be better off contacting Fenix and seeing if they can repair your light. Or perhaps buy a new light.

The driver is in the head as well, and much more likely to be the source of a failure than the LED.

But in either case, getting the pill out will take torque, and maybe heat. A blowtorch might be a bit much - maybe a hair dryer, or very careful use of a heat gun.

The last Fenix I tried to remove the pill from to change the LED was as small 1xAA one from a year or two ago.

They used so much threadlocker the pill was impossible to remove. I ended up destroying the driver so I could stick needle-nosed pliers in the bottom of the pill. The pill was deforming and bending, but it never budged. Definitely a LOT of threadlocker in there.

Before that I had the same issue with a tiny 1xAAA Fenix. But that little was small enough that I was able to get enough torque to break the threadlocker. It was close though... my pliers were bending and I was worried they would break before the threadlocker.

Removing the pill from a larger Fenix light through just torque is probably impossible. I think the aluminum will deform before the threadlocker gives way. The only realistic way to do it is to heat it up with a blowtorch to soften the threadlocker.

According to Permatex, the red threadlocker requires apply localized heat to 260*C/ 500*F, and disassemble while hot. I don't think it's worth going through all that to try and fix it yourself.

Docs
Permatex: https://www.permatex.com/wp-content/uploads/tech_docs/tds/27010.pdf

Henkel: https://dm.henkel-dam.com/is/conten...-Red-271-Carded-Tube-0.20-fl-oz-2018-04-09pdf

Heat the head and unscrew aluminium reflector from behind. Use pliers on 2 small holes.
I've done it with my TK75 years ago.
Driver is in battery carrier, so 100% led died.
I found pics of mine: https://www.torch.pl/forum/index.php/topic,58412.msg232143.html#msg232143
That could help.
Mike