BLF X1 clone acting weird

I have 2 of these drivers

They act like Bistro UI, but do not achieve proper power. Out of 7 basic modes, only 1(moon) ,2,3,4 gain brightness. 5,6,7 remain as bright as 4.
I’ve double checked everything that came up to my mind. I did trials on 2 drivers, with 2 different leds. Doing everything with due diligence.
Investigating the reason I srtiped down to just led, driver, battery and wire between batt. “-” and pill. The error occurs already here.
What do you think? Am I doing something wrong (I’ve already dealt with this driver many times, that had never happened before)? Or my 2 drivers are broken in the same manner?

If there is not some huge resistence in your circuit somewhere, or use an unusual high voltage led, it sounds like the FET is not working. It could be a soldering problem, I would first check if the gate does not connect to the MCU.

I don’t think I know how to check the gate.
I used XM-L2 and XP-G3.
I think I might have shorted the circuit with a reflector. Although I always stick isolation tape on the bottom, the tape bears marks done by soldering joints. I lowered the joints, but it’s typical problem for 16mm pcbs.

Can a short circuit break the FET? Is it likely to happen twice in a row?

These drivers look exact like the ones in the BLF A6. And from what I have read, the UI is the same.
Seems like the programming works, but the execution is flawed.
The lower modes are driven by the single 7135, the rest by the FET.
The performance of the FET is best at the lowest possible total resistance in the system.

Issues I have encountered in my very modest experience are:

- the driver does not fit snug in its cavity. Clean cavity and driver and see to it that it sits “at the bottom”.

- the standard leads are 24AWG. You maight wanna swap them for 22AWG or even 20AWG.
because they are quite thin an can get a lot of abuse in the modding process, they may even (partially) break.

  • and while you are at it: bypass the driver spring.

All this is only relevant if the FET is not dead. A dead FET is like a dead horse, no use whipping it.