Bradwellguy said:
I have just fitted a 1000w mid drive, I did not order a display not knowing I needed one to operate it. So I fitted a KD58C display. But the motor still do not turn on as do not the display. I tried a SW102 display, same outcome. Could it be the controller? I have started a discussion with the chinese supplier, but translation is awkward. Any ideas? This is my 3rd E bike build, but first 2 were hub type.
If nothing turns on, the most likely problem is the battery itself, or the connection between battery and controller. Or a battery that is the incorrect voltage for the controller, either too high or too low.
If you've already verified that is not the problem, then links to the sale page for each part you purchased (battery, controller, motor, display, and every other part being used in the electrical system) may help us help you figure it out, based on info from each part's page.
Note that if a controller requires a display to operate it, you need to get the specific one it requires; the one it normally comes with is the best option as it will be compatible, while any other display may be incompatible, in any or all of: wiring, communications protocol, menu settings available, firmware version, etc. Unfortunately many display/controller combinations are not compatible.
Also a diagram of exactly how you have it wired up (not how they tell you to, but how you actually wired it, tracing out each wire (or at least each cable if not individually wired) and drawing it up) is helpful not just to see how it's really wired (in case something is wrong), but also for the future so you will know what to reconnect should anything become disconnected or changed.
FWIW, most controllers that "require" a display will actually operate without it, but they will only work in default mode, which may not be it's full power, and you won't be able to change any settings to make it do things differently. Typically you would need to jumper across two pins in the display connector to pass battery power from one of them to the other to enable the controller. Which pins those are may vary from system to system, and you don't want ot just try things randomly because the battery voltage will destroy the controller if you connect it to the TX or RX or other 5v-level signals it may have in the connector.
