Bafang M510 will not start

[Lotus Emira]

Hi. I built a Dengfu E10. Motor started when in components, but dislay will not turn on after assemby and I am not getting assist.
Checked the voltage input. Was 32v? when off and 52v when on, but after that I do not know what to test.
They are simple connections. Pushed in the plugs several times best as I could, but what I remember I have only 3 active plugs.
I think is speed sensor running to back wheel, power (yellow)and display controller. (green)
From the contoller it routes through to the on/off and assist settings controller. (No throttle installed)
Could the controller be broken? How do I measure a CAN connection?
I did order a new controller/display on Ali. (want to merge the assist controls with display) but do these displays break? I can't imagine anything breaking during install.

 

[MrFixit]

It could be the two pins in the battery support bracket located in the bottom of the frame, they connect to the battery On/off switch. The pins stick and don’t make a connection, it’s a common issue. I connected the battery terminals with a piece of wire then taped over that, the pins then keep the wire in place when the battery is inserted into the frame, that solved it for me. Others have removed the battery from the case and soldered the wires together for a permanent fix.

 

[Lotus Emira]

How does that help? As I mentioned, it's getting 52v.

 

[MrFixit]

All I know is that the connection between the pins and the battery can be intermittent, maybe that’s why you can get a reading?

 

[Lotus Emira]

All I know is that the connection between the pins and the battery can be intermittent, maybe that’s why you can get a reading?

No, the 52v is nice and stable. I suspect the connection/display, but I don't have spares or ways to check as it is not a simple +/- wire

 

[MrFixit]

Sorry I can’t help any further, you may be able to get spares from hollandbikeshop.com
or green bike kit or Ali Express