Kunteng Controller : lights always on ?

My Kunteng controller used to have a functional integrated ON/OFF switch that I was controlling using my Eggrider.

Now, it is always on, even when the Eggrider is OFF.

I made some "surgery" inside the controller to add features but never touch concerning wires except to add a 5V regulator to power my USB led.

Eggrider is fine, I tested it with another kunteng controller and I works perfectly.

Any clue to solve this ?

Best