Uniquefire UF-2100 3-mode conversion to 5-modes

BLF member Bequerelio posted a link in another thread to forolinternas.com where they discovered that a UF-2100 can be converted to 5-modes. The pics didn't really show well what was done and the conversion from Spanish to English doesn't help much either. I decided to try it and it is still amazingly easy. I wasn't able to take pics while I did mine but it is easier to just describe what needs to be done.

To do the mod you need needle nose pliers (to remove the pill from the head), a soldering iron, and desoldering braid or solder sucker.

  1. Unscrew the flashlight head from the body.
  2. Unscrew the pill from the head.
  3. Remove brass retaining ring from the rear of pill exposing the driver PCB.
  4. Pull driver free from pill to expose the internal side of PCB without damaging the wires.
  5. The IC chip is the larger chip on the board and has eight legs, four on each side. One side will be at the outer edge of the PCB. This is the side we will work on.
  6. Looking at the four legs at the edge of the PCB you will see that the 2nd leg from the right will have a solder bridge connecting that leg to the outter ring of the PCB. Warm up your soldering iron then, using your desoldering braid, or solder sucker, remove the solder bridge but be sure not to desolder the chip leg to it's mounting point.
  7. With the soldering bridge removed, put the PCB back into position and press the brass ring securely back ino position making sure you have it tight against the PCB.
  8. Replace the pill back into the head and reassemble the light.
  9. Enjoy your 5 modes!

Thanks JohnnyMac, I will try it out later.

Did you take AMP measurements prior and post operation?

From what i can gather, people were noticing the high mode dropping all the way down to 1.33A(as the 5 mode) from 2.8A(as the 3 mode)

I can’t take amp measurements but I compared it to my 3A driven jaws light before I did the mod and it’s still the same brightness after the mod so I don’t see any difference in output at all. It’s still bright as hell.

I suppose if you did see a difference you could just solder the bridge back and go back to where it was at 3-modes. I don't see any difference in mine.

It's me Heke not Bequerelio

The leg N-3 (GP4) of PIC 12F629 mut be disconnected to get 5 mode

Is good to measure the Amp/h before and after, must be the same.

The leg of PIC microprocesor is conected to ground, you must remove the solder of leg N-3 and the flashligh run in 5 modes, if don't want the mode... solder again this pin and return to 3 mode.

In this pict you can see the solder to remove (red circle)

That's all folks... Easy, fast and cheap.

You can see the pin 3 dsconnected from ground:

I use desoldering wire to remove the tin:

This pict is in HIGH mode before the mod (HIGH-LOW-BLINK)

This one is HIGH after the mod to 5 mode (HIGH-MED-LOW-BLINK-SOS)

3 mode: HIGH--> 2,77A LOW--> 0,089 BLINK--> Not measured

5 mode: HIGH--> 2,83A MED--> 1,38A LOW--> 0,09 BLINK--> Not measured SOS--> Not measured

The small differences are for the voltage of the battery 4,11 -- 4,22 V.


Thanks for adding the pics and tail cap measurements, Heke! It's truly an awesome mod and if anyone who has a 5-mode would be willing to look, I'm betting they can be converted to 3-mode (not that they'd want to). Definitely no need to pay more for the 5-mode as they are likely the same exact product.

I wanna convert mine to 3-mode... High, medium and low ;)

Looks like i'll probably mod mine when it comes in :)

Does anyone have a 1mode and can you do the same thing and make it a 3 or 5mode?

There is no drop in high mode current (could be as high as 4.4A on my Sanyo 2600, you need to push it hard into the spring) after modding from 3-mode to 5-mode.

can you just snip the leg of the chip ?

- Does anyone know about the kingston version of this light..kingston is the one replacing the uniquefire ..hopefully it's just a name change

How do you get the brass ring securely back on? It's hard.

There is a flat side and a curved side, which goes where?

awesome! the lack of medium was kind of annoying on the 3 mode..hi med low would be perfect but ill take the 5 mode for the medium..thanks so much for this!

Flat side goes against driver. I use a pair of smooth jawed slip-joint pliers to press the ring in place working my way around the pill a litle at a time until fully seated. Don’t press the ring fully from one spot or you will distort the ring. Think of it like tightening a head gasket or wheel on your car. If not tight against the driver it will not work reliably or at all.

I did it with my godzilla grip fingers. They still hurt.

Has someone tried to freeze it?

Probably putting it (the ring) in the freezer, for effect of the expansion with the heat and contraction with the cold, contract a bit

Anyone? Recently ordered this from DD and would like to know if it's the same.

Solarforce clip works with the UF-2100

First things first. How did you get it off?

I used the tip of a small pocket knife and worked in under enough to get a small gap. I then used a small screwdriver and twisted and poppedy it off. It’s not easy to get it started but once you manage to get a gap it’s cake from there.