Help identify display wiring

[boltyk]

Hi,

Maybe someone can help to identify wiring on the display? Kid dropped the scooter and all command wires got broken.
It's an old scooter. No marking on it - nothing.
24V. Has break and throttle levers. 3 speed modes. Switch between speed modes by pressing once on the button.
Display shows level of throttle and level of brake on sides.
Also shows odometer, trip and voltage (to switch between them you need to hold button for a little bit, then second quick click)
3 button clicks to turn on/off the headlamp.
I think it's from UK or Europe as the distance is in km and speed is in km/h.
Also found this one in the UK shop, but support is not helpful - old scooter, nobody knows what it is.

E-Scooter EX400 Foldable Electric Scooter – Colour LED Screen

E-Scooter EX400 Foldable Electric Scooter. Colour LED Screen for information display. Powerful Silent 250w motor. 5.5inch Tyre Size. Free next day Delivery.

www.segbo.co.uk

Display is in the round casing, one button aside for all operations. Lenzod and V11-20171913 - the only marks on the board.
green/blue wires form the controller feels like rx, tx.
As three others (red, black, yellow) are on a separate connector from the controller and power related (28V between yellow and black and also between yellow and red. nothing between red and black - so the yellow is + then?) - these are colors on the controller connector.
On the display board these controller wires go to 5 pins on P1.
The middle one (currently black wire) connected to the right pin of brake/throttle (P3 and the one above Lenzod logo) and for these both the wire colors are (from the left pin) - black, yellow, red - so red is ground??? (connected to big areas on the board)
The currently yellow one from the P1 goes to the button (leftovers of it are on the left of CS1621CGO chip).
Another side of the button connected to the middle of P1 (currently black) so when you press the button it connects 3rd (black) and 5th (yellow) pins.

It was a fully functional scooter till that incident

 

[fill]

If yellow has the battery +ve voltage, i suspect that when turned on this will be connected to red to power on the controller(silver box). with the ebike controllers i am slightly more familiar with (still no expert) this is a common state. though wire colours are usually red/blue often populating pins #1 and #2, tho its not a standard afaik. if correct this should turn on the system and provide you with throttle and brake cut off control even if no display info is shown. A $5 ebike volt meter can provide battery info if needed and a phone/gps app can provide speed if needed.. tho you may not wish to trust younger kids with a phone at speed ??

controllers are generally paired with the display i/o units and if sold within a regulated market could easily have 'custom/hobbled' f/w installed to cap speeds etc to comply with local regs, making substituting an off the shelf display more problematic.. So often the simple fix is to replace the controller and display, and if taking this route buy both as a bundle Not separately to avoid possible coms conflicts.

 

[boltyk]

Looked up by chip datasheet for AMS1117 the leg near the dot is GND, and it is connected to the pin3 of the display.
So it is surely ground.
But how to identify ground on the 3 pin connector from the controller?
I assume, as I have voltage between yellow and black and yellow and red - yellow is a P+? So black and red are grounds?
Feels like I need to open controller too to figure where these 3pin connector is going to/from.

 

[fill]

Test the continuity between red/black/yellow and the battery input terminals perhaps?

 

[boltyk]

Battery input terminals - is it a charging port?

 

[fill]

Battery input terminals - is it a charging port?

Yeah - I forgot the above pics which seem to indicate the battery, controller, and display are all in one casing?? while the norm is 3 x discrete units wired/plugged together, and my suggestion would have related to terminals the 'removable' battery would plug into.

IF an all in one not quite he same, and would require significant disassembly to isolate the control system from the battery.

 

[boltyk]

Battery, controller and display can be separated, as they have usual plugs wrapped in shrink tubes.
Is there a difference between charging port going to the battery and the fat plug going to the controller?

 

[fill]

both should be connected to the cells via different paths through the bms protection, so ideally yes, but possibly not if not conventionally wired. So just unplug the battery to test where the battery did connect for continuity with the connections to the unknown solder points. it may illuminate the main power/ground connections and eliminate false positives set to a state for system initialisation? tho may not.. ?

failure to find a 'lock' connection between the display pcb and the controller pcb to hack the display and run headless with speed control, will probably require a controller replacement for an easy fix, probably circa 20+usd? for the most basic simple generic controller..

 

[fill]

Penny just dropped this end If no mechanical isolating switch between battery and the controller UNPLUG THE BATTERY NOW!! If you have actual battery voltage connected to the damaged pcb anything shorted regardless of resilience has been long cooked.. And its a REAL fire risk.. ok not as much of a risk as an actually damaged battery but a close 2nd imho..

with ALL EV's no matter how small.. - ANY damage anything to do with power electrics etc.. #1 priority in all circumstances DISCONNECT THE BATTERY.

That should have registered earlier.. my bad..

 

[boltyk]

It's possible I already cooked something with experiments as the battery was not disconnected.

 

[fill]

Well its disconnected now and nothing burnt down so its still a win
something like this could sort you out..

 

[boltyk]

Your link is 404, but yeah, I ordered controller + display kit for 24V already.
All main connectors (battery, motor, hall for motor) looks alike - so hopefully it will be all compatible and kid have a working scooter again
While this kit coming from China - continue having fun trying to figure and fix this one and I already learnt a lot!

 

[fill]

Take it slow, and if you hit a rd block take pics n post back.. its all pretty modular and thus plug n play.. you may need to crimp/solder connections if plugs dont match but taken 1 by 1 thats just time.. good luck.

 

[boltyk]

Saw some displays with several prone green connector - is it a new kind of a standard?
https://www.aliexpress.us/item/3256...JtF0CcUG&utparam-url=scene:search|query_from:
Looks similar to what I have - I can see throttle and break 3 wire connectors. 2 prone I assume maybe light.
But the controller connector has only 4 wires as I can see.

 

[fill]

Thought you had bought a kit? controllers and displays are best sourced together as both need to 'speak'/ run the same code to talk together.. buying as a bundle is the the easiest way to be sure to get compatible controller/display combo.
the display in your kit bundle should have all the required connectors.


Thats a display is for a Branded Segway Ninebot models ES1, ES2, ES3, and ES4. ONLY!! why should it have the same number of connectors as your completely different make/model generic controller kit?

however ebike/scooter controllers can use a number of different connectors, the look like a good idea 'waterproof' styles of connectors ( Julet, Higo etc) are a PITA when it comes to problem solving due to the tiny pin dimensions and making good connections with meter probes

 

[boltyk]

Yeah, I bought a kit (controller + display).
Tiny pins and connectors are big problems for sure! For this custom scooter for example the case for the display is so thin they soldered small extensions from the display board cause soldering receiving connectors to the board wouldn't fit into the casing. And these wires are so small and fragile - omfg! several touches - it falls out. That's why I have this wiring problem in the first place.