Trouble with Eagtac sx25l3

Hi!

Friend asked me to take a look his light, it does not work properly.

I can find some modes and by twisting head I can get strobes, beacon etc.

Light is very dim.

ALL contact points have been cleaned with alcohol.

Driver is checked visually and some wires “beeped” with multimeter.
Nothing seems burned, cold soldered or disconnected.

Several sets of good quality batteries have been used to test.

All parts are screwed down firmly enough.

Good suggestions are much appreciated!!!

P.S. possible to get spares for these :weary:

you can check the diode with an external power source like a 9V battery
and check the voltage on the LED when driver is on

could be a buck driver on 3S, so many things can have seized function on the driver even if they are optically ok