i have LED 810 model for some time. it is working and driving the motor correctly. green wire has 1 2 3volts respectively when switched the modes but it is not connected on controller side. why? i bought this from FOCAN store over aliexpress.
black and red wire is enough to operate this panel as on off switch and light switch, that is all. blue is for nothing. i cut it. it made no difference. once i had a bike with 880 panel ( three years ago). all wires had someting to do. i remember that i managed to reduce voltage of PAS levels using a single diode by 0.5 volts and this was giving me a slower riding possibility at level 1. rest was powerfull enough to move faster.
What you're saying isn't quite right.
The red and black wires power the panel with battery voltage. The on/off switch operates both the panel and the controller. When switched on, the red wire is latched to the blue one to provide the battery voltage that powers the controller. The controller is powered by that blue wire, so if you cut it, the controller would have no power and wouldn't work unless you hot-wired it somehow..
The green wire sets the assist levels. If it's not connected, you only get level 1. The throttle works independently as long as the controller is switched on.
Nearly all Chinese controllers in the last 10 years read the pedal sensor and look for a yes/no condition of pulsing or not, so cutting down the 5v signal to 4.5v would make no difference. Before that, there were all sorts of weird systems, some of which are still around, like the guy's Izip (Currie) that he's trying to sort out in another thread.
It sounds to me like either you had the wrong controller for the panel or it was wired completely wrongly.