Battery connector causes shutoffs

funnel

Member
May 15, 2020
69
26
World
The bike is the Stereo Hybrid 140SLX. I bought this bike less than 4 weeks ago and I have experienced random shutoffs during riding, mostly when going uphill. When it shuts down the solution is just to remove the battery and put it back in and it works fine till the end of the ride. When it happens and come home I clean the contacts with a qtip and isopropyl alcohol. It then seems to work for about 70-100km and the cyle repeats. I also see the connector has some slight play in the battery tray, but I guess this is normal, not sure. The connectors seem pretty worn out for such a new bike.

Did anybody have the same issues and how you solved it? Or do you have any ideas how to clean the contacts properly for good?

Thanks for all suggestions.

1.PNG 2.PNG 3.PNG 4.PNG
 

Hattori-Hanzo

Well-known member
Apr 10, 2023
428
568
UK
I had a random issue today with my new hybrid 160. Bike was fantastic all day then I got caught in heavy rain on the way home and the motor stopped assisting. Kiox display was working fine but motor would no assist in any mode.
I turned the system off for 30 seconds then back on again and every thing seemed normal again.

Anyone else had the same?

When I got home I checked the battery tray for water but it all seemed dry. I also noticed the battery connector in the frame had some play so I assume this is normal too.

I have seen a few posts where people use foam inside the battery tray to hold the battery firm.
I do notice when installing my battery that it clicks into position once with the toggle on the battery and then again with the key, but if I push inwards on the battery there is a few millimetres of play. Again I assumed this was normal and intended movement? why would they not fit some foam padding from the factory if not the case?

I did see on post where someone had filed the tab on the lock to allow another click of the batter to secure it tightly into the tray but this seemed a bit excessive to me and would totally void the warranty.
 

RustyIron

E*POWAH Elite World Champion
Subscriber
Jun 5, 2021
1,865
2,926
La Habra, California
remove the battery and put it back in and it works fine

Beware the pitfall of imagining a potential cause, and fixating on that one thing. Really, we can only be certain of one thing: your bike fails intermittently. We're sure of that and can write it down in ink.

Our next observation is that when you remove the battery and then reinstall the battery, the bike resumes functioning as normal. Can we conclude anything from that?. Is it possible that there is high resistance at the connector? It's possible, but since you've addressed that several times already, it's not probable. Could the cause of the failure be something else? Absolutely. There are dozens of different things that can cause your bike to stop working.

The best way to troubleshoot an intermittent anomaly is to look for the cause when the problem occurs. Now is the time to be proactive: learn how to read the diagnostic and trouble codes from your system. Then you'll be prepared next time your bike dies on the trail.

Address the bike as you would your desktop computer. Suppose the computer crashes every couple days. You get on the phone with the service department, and the voice on the other end suggests that you unplug your computer and then plug it back in. Voilà! The computer runs fine. Is the problem the plug? The wall socket? It's entirely possible, but you and I both know that your computer will probably crash again some time soon.

Look into reading the diagnostics. If Cube considers this "top secret" and you can't find anything, then start addressing other likely causes of failure. There are plenty of electrical connections on a bike. That's not an unreasonable place to start.
 

Mikerb

E*POWAH Elite World Champion
May 16, 2019
6,628
5,104
Weymouth
To add to the above..............." Kiox was still working fine but no motor assist"......................this coincided with heavy rain.
So..................
1. the bike was still powered up because the Kiox was working so unlikely anything to do with battery connection.
2. the motor stopped assisting ...in any mode....so mode change was still working as well...more evidence nothing wrong with the battery connection.
3. What stops the motor from assisting?? you go faster than 15.5 mph............or it fails to get a speed reading from the sensor.
4. Why did the motor start assisting again after swiching off and restarting the system? When the motor failed to get a sensor speed reading it stopped assisting .............restarting acted like a computer reboot.
5. This failure happened in heavy rain.................I suspect the magnet or speed sensor became fouled.
 

Hattori-Hanzo

Well-known member
Apr 10, 2023
428
568
UK
Thanks for the input Mike, that seems like a very plausible reason, fingers crossed that's all it was.
going for another spin tomorrow to check it over (y)

Funnel, those connectors do look a little suspicious, could it be an over heating issue?
Though I thought the kiox would display an error code if this was the case?
 

funnel

Member
May 15, 2020
69
26
World
Thanks for the input Mike, that seems like a very plausible reason, fingers crossed that's all it was.
going for another spin tomorrow to check it over (y)

Funnel, those connectors do look a little suspicious, could it be an over heating issue?
Though I thought the kiox would display an error code if this was the case?
No. There were no errors. Just intermittent twitching for a few seconds and then the motor and Kiox shut off. Also removing the Kiox and cleaning the contacts didn't help in any way.
 

Hattori-Hanzo

Well-known member
Apr 10, 2023
428
568
UK
As rusty says the first thing to check is all accessable wiring, from the controller to the motor.
Unplug connections one at a time and inspect/grease them.

Also check the entire length of the cables for breaks/splits, especially around the head stock and motor.

If still no luck after that I'd put it down to a warranty job.
With not much to go on your chasing a fault that could be any where in the system, on a new bike that shouldn't be down to you to solve.

I hope you get it sorted asap, keep us posted with how you get on.
 

SteveTTT

Member
Mar 15, 2022
49
35
Hampshire, UK
Similar issue on a Giant Trance turned out to a “battery management system” fault according to my LBS. Battery replaced under warranty. A mate had an identical issue and the same fix. I guess that makes it a firmware issue?
 

funnel

Member
May 15, 2020
69
26
World
I cleaned the connector as good as possible with true contact cleaner and gently scraped of a little bit of black residue with tweezers on one side that wouldn't come off with just contact cleaner.

Then I put some neoprene self adhesive tape around the connector to prevent it from rattling mid driving and cause arcing. I didn't fully fix it and It still can move when removing the battery if needed.

I managed to do about 170km on various dusty and wet terrain and all seems good for now. Hopefully this was the solution.

5.PNG
 

funnel

Member
May 15, 2020
69
26
World
Verify if display, remote, etc cable conectors are not losse.
I verified all the connections from the remote/kiox to the motor. All where plugged securely on both sides. My issue was definetly at the connector of the motor to the battery. I made about 300km now and all works without any issues. I won't remove the battery or touch anything as long as it works to see how long it lasts.
 

funnel

Member
May 15, 2020
69
26
World
Just an update. After 2300km of rides the shut off happened once again. I recleaned the battery contacts and hopefully I manage to get another 2000+km without needing to do anything.
 

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