Confused and looking for 48v 250w rear hub since Yose won't sell me 250w 36v kit with 15ah battery

[Waspy]

Well, I'm no expert but the first thing you need to do is charge the battery. It should be 42v fully charged and 32v fully discharged.

 

[saneagle]

First step would be to charge the battery to the normal 42v or close. If it doesn't go that high, something is wrong with it. Charge it disconnected from the bike.

While it's charging, test the MOSFETs in the controller with a meter set to resistance. It's very simple. Disconnect everything then put your red probe on the red battery wire and your black one on each of the three phase wires. All three should read the same, somewhere between 5k and 20k. Repeat with your red probe on the black battery wire.

 

[Nealh]

Check the battery voltage , tbh matters not if it is charged or not. One should see more then the 23v indicated by the display.
The 23v registered on the display is likely a controller failure and a voltage regulator failure , the events are pretty much exactly the same I had years ago with a Lishui controller /display when I had the Oxydrive kit. Both my batteries at the time were near fully charged, just a case of a duff controller.
It was a turning point for me and I upgraded and fitted a better KT system and haven't looked back since.

 

[throwawaychap]

Hello everyone, I took a bit of a hiatus because I've been really busy with other matters.

I contacted Yose 2 days ago. And they have been replying to my queries. Last they said they will have their engineers simulate the symptoms I've described to find the fault.


First of all I haven't done what Waspy, Saneagle and Nealh said yet because I've only just read the posts now.

A few more things:

The bike worked perfectly and faultlessly up until that Thursday.

The 23v voltage it showed was only at that exact moment once I stopped and switched off the bike and switched it on again.

Since then, every time I switched the system on the displayed showed the actual battery voltage. Either 36.5v or 39v after I charged it a bit.

There was no error code displayed on the screen at any given time.

I tested my brake sensors by pressing them levers and letting go off each individually when I switched on the bike - and only then I saw the 25 error code as expected. So they're working normally.

Last Sunday, when I disconnected every cable and connected back again, I switched the bike on, lifted it and ran it on the throttle for about 5 minutes - it worked as normal. The battery voltage displayed the voltage expected after I charged it for an hour.

Immediately after that I took it for a test ride and the bike worked as normal for about 10 minutes and then it switched itself off as I was pedalling, much like what happened on the way back of my commute that Thursday. I stopped, waited a bit, switched the system on again, proceeded to pedal and the bike switched itself off again after about a minute.

Since then, the bike has been in my garage and I have struggled to even switch it on. Meaning, when I press and hold the button on the display, it lights up for a fraction of a second and shuts itself off again.

Only once yesterday was I able to switch the bike on without that happening.

PS.

I will try fully charging my battery today. It usually goes up to 41.3v or 41.4v when fully charged.

 

[throwawaychap]

Update:

I charged the battery to its full capacity (green light on charger).

After many attempts to switch the bike on, it read 41.4v - which is what it normally showed when the battery was fully charged previously.

What caught my eye was, as I was repeatedly pressing and holding the button to switch the system on, it would turn itself off after a fraction of a second but this time, as it did that, the display faintly showed the battery was 'empty', it had like one bar or zero bars - I couldn't read the voltage.

But mere seconds later I succeeded in switching it on and it read 41.4v as I said. 5 full bars.

Intuition tells me it could be the battery cable that came with the kit, it's a 2 bullet points to 2-pin julet that connects to the controller
(see attached image)

But it could also be the controller?

Also, would I still be able to perform the aforementioned tests if my controller has that julet/waterproof connector?
(image also attached, obviously the battery cable is the one with the 2 protruding pins)

Alas, I don't even have the tool(s) necessary for the job.

I'm puzzled but, since a few days have passed I'm calmer. The kit and the battery are well under warranty since I've only had it since late January - hopefully I'll get it resolved. Fingers crossed.

 

[saneagle]

Update:

I charged the battery to its full capacity (green light on charger).

After many attempts to switch the bike on, it read 41.4v - which is what it normally showed when the battery was fully charged previously.

What caught my eye was, as I was repeatedly pressing and holding the button to switch the system on, it would turn itself off after a fraction of a second but this time, as it did that, the display faintly showed the battery was 'empty', it had like one bar or zero bars - I couldn't read the voltage.

But mere seconds later I succeeded in switching it on and it read 41.4v as I said. 5 full bars.

Intuition tells me it could be the battery cable that came with the kit, it's a 2 bullet points to 2-pin julet that connects to the controller
(see attached image)

But it could also be the controller?

Also, would I still be able to perform the aforementioned tests if my controller has that julet/waterproof connector?
(image also attached, obviously the battery cable is the one with the 2 protruding pins)

Alas, I don't even have the tool(s) necessary for the job.

I'm puzzled but, since a few days have passed I'm calmer. The kit and the battery are well under warranty since I've only had it since late January - hopefully I'll get it resolved. Fingers crossed.

Which switch were you pressing? You can't take any notice of transients on the LCD because the capacitors in the controller will power it for a second or so.