problem after replacing the control panel


New Member
hello all,
i have a problem with my electric bike and i need your help:
the original control display was damaged(model 450u-manual attached) but he is still functional and operates the bike i just cannot see the details on the display...
so i have decided to buy a new one which is the KT-LCD3(manual attached), the wirings are identical in both.
after i have connected the new control display i have a strange symptom: the bikes works for a few seconds then stops, then i need to shut down the display and turn it on again and i get the same results ...i have a video this is the link:
i have configured the display as accurate as i can possibly know but maybe i'm missing something here..
need your advice...



Well-Known Member
I didn't know the LCD3 display would interchange with other brands.

The 450u manual shows that it was designed for 24 and 36 volt systems. I know the LCD3 will run 36 or 48, not so sure they will run on 24v, especially the newer ones. What I'm wondering is regarding the potential for the LCD3 to be sensing low voltage and shutting the motor down to protect the battery - whether it should do that or not.

Have you set the LVC (low voltage cutoff) parameters in the LCD3 setup? (C 12)
Is your battery fully charged, to the point the voltage level is high enough to prevent the LCD3 LVC from kicking out?

What, exactly, is the battery voltage right now?


Well-Known Member
You may well have the right display for your controller but I'm dubious. The LCD3 is made for a Kunteng controller. It might work with other brands that have copied the Kunteng design, and that would not be unusual for China, but your display appears to be from Taiwan. Unless Kunteng copied them....

The wiring is about the same for all of these LCD displays. Battery power, ground, a controller start lead (connect to battery) and two serial data lines, but every manufacturer will have their own serial protocol.

If battery/ground are in the right spot, they will power up. If the ignition is in the right place, the controller will start up. After that, the data has to match.

I own the LCD3, an SW900, and a Brainpower display and they will all power up with just the battery/ground. They have the same plugs and can be interchanged. You can enter the program mode and change settings, but unless they're talking to a controller that understands them, nothing productive will happen.

At the same time many controllers will start up if you cross the ignition wire to battery, Some of them will also default into a single PAS level, and the throttle will work. Sometimes the manual instructs you to loop the data lines together. Kunteng contollers are often shipped with a connector plug that is strapped like that, and those will run w/o a display with a single PAS and active throttle.


New Member
Wow...that is incredible, i wasn't expecting for such a quick and professional answer. I thank you for your effort. So if i understood correctly what i need to do is to buy the exact control display as the original and that should work. To be honest i just need the bike to ride i don't care about the it possible to buy something simple that will just fire up and work??...the display aslo controls the lights...i should take that into consideration too...