Ezee quando 7 flashes error

[hungrv1]

Hello,
I got a strange error on my Ezee Quando. My Quando is on running but I decided to switch the battery with my wife Quando also ebike to ride further. Immediately my bike can not run while her battery still full. Reading number of flashing in controller, I counted 7, it means high voltage battery. Very surprise since battery runs normally in my wife's EZee Quando bike. Went home and checked all batteries voltage, it showed around 40- 42v. Got the battery full charge over night with an expectation that the controller will stabilise over night. However, it still got 7 flashes error. Can any body advise me how to fix this error.? If I buy an old Quando ebike (as shown in photo) to use its controller. Will it work for my Quando ebike. My bike is not the first Quando as shown in photo, not Quando II but quite old, around 12 years ago. Many thanks, Hung.

 

[flecc]

This can happen between two Ezee bikes, I've suffered it myself. It's due to controller and charger variations.

Just drain the wife's battery slightly in her bike to drop the voltage a little and then it will run in yours.

In future try only using your charger on the wife's battery if you want to use it on your bike, no need to buy that old Quando model.
.

 

[hungrv1]

This can happen between two Ezee bikes, I've suffered it myself. It's due to controller and charger variations.

Just drain the wife's battery slightly in her bike to drop the voltage a little and then it will run in yours.

In future try only using your charger on the wife's battery if you want to use it on your bike, no need to buy that old Quando model.
.

Hi Flecc,
I read many your advice in this forum but this is thefirsttime I get your advice quickly. Much appreciate!! I will try your advice.
Just some notes: We always charge both batteries at the same charger. At that time the voltage on my battery is around 40v but my wife's battery is 42.8v. I need to go for another trip so I swapped my battery with my wife as we normally do. But surprisingly, it caused a trouble this time. I put my battery back ( at that time around 40v voltage) but still 7 flashes. Will try to drain my battery down to ~40v and try again to see what happen.
Thank you very much,
Hung.

 

[flecc]

Hi Flecc,
I read many your advice in this forum but this is thefirsttime I get your advice quickly. Much appreciate!! I will try your advice.
Just some notes: We always charge both batteries at the same charger. At that time the voltage on my battery is around 40v but my wife's battery is 42.8v. I need to go for another trip so I swapped my battery with my wife as we normally do. But surprisingly, it caused a trouble this time. I put my battery back ( at that time around 40v voltage) but still 7 flashes. Will try to drain my battery down to ~40v and try again to see what happen.
Thank you very much,
Hung.

The difference in voltage between it working and not working is very small, in my case less than half a volt. 42.8 volts is too high.

Let us know how you get on.
.

 

[hungrv1]

This can happen between two Ezee bikes, I've suffered it myself. It's due to controller and charger variations.

Just drain the wife's battery slightly in her bike to drop the voltage a little and then it will run in yours.

In future try only using your charger on the wife's battery if you want to use it on your bike, no need to buy that old Quando model.
.

Hi Flecc,
Unfortunately my Quanfo still get 7 flashes error even I drakndd the battery to 37v voltage as shown in the photo. Do you have any advice for me in this case? Thank you!

 

[flecc]

That's very odd and clearly a different case from the one I suffered. Since your Quando runs ok on your own battery when fully charged, there's perhaps something like a minor fault mismatching between your controller and the BMS in your wife's nominally identical battery which is ok on her Quando.

But I have absolutely no idea what that is.
.

 

[Nealh]

The battery that charges to 42.8v needs the charger looking at and checking as the over voltage could cause an issue, some chargers can be adjusted via the voltage trim pot usually found inside of said controller. Cell self venting or internal damage could occur.

 

[flecc]

From Neal's advice and as you are using only one charger, you could switch to only using the other bike's charger on both batteries to give the lower terminal voltage, but it seems that won't change your being unable to use the wife's battery.
.

 

[hungrv1]

I have another charger but I am afraid the trouble is not from the voltage as notice ld by the controller. I tried 37.2v, 40v and 42v voltage battery formg bike. But it still shows 7 flashes errir( high voltage error). I now think abot replacing the controller. Ebay seller get one for £50 but I am mot sure it works for my bike or not since my controller's serial number damaged. Do you think a controller from old Quando version can work on my bike as shown in photos. Thanks.

 

[vfr400]

After careful thought, the only logical cause I can think of is that the voltage is noisy on the faulty battery. You'd have to put it on an oscilloscope to confirm that. My memory is bad these days, but I've got a feeling that I've seen ferrite cores on some bikes, possibily Ezee, to smooth out the supply. I thought that they were to cut down emissions, but maybe they use them to stabilise the voltage for functional reasons.

You could try one of these. Wrap one of the battery wires (positive red wire) through the centre and looped around and back through it to see if it helps.

https://uk.farnell.com/multicomp/33ri-20x10x10/ferrite-core-cylindrical-120-ohm/dp/9640398

Another thing to try is a big capacitor fitted directly across the battery supply. Any large capacitor with a rating of 50v or more would do. The controllers already have such capacitors in them, but maybe one is compromised in some way, so it can't filter properly.

 

[flecc]

The controllers were always one type on the earlier Bafang motored Quandos lik yours, so are interchangeable. However another one might not cure the problem.
.

 

[hungrv1]

The controllers were always one type on the earlier Bafang motored Quandos lik yours, so are interchangeable. However another one might not cure the problem.
.

Hi Flecc, what did you mean that "another one might not cure the problem." Do you think the controller on the older version of my Quando can wirk on my Quando. Thanks.

 

[hungrv1]

After careful thought, the only logical cause I can think of is that the voltage is noisy on the faulty battery. You'd have to put it on an oscilloscope to confirm that. My memory is bad these days, but I've got a feeling that I've seen ferrite cores on some bikes, possibily Ezee, to smooth out the supply. I thought that they were to cut down emissions, but maybe they use them to stabilise the voltage for functional reasons.

You could try one of these. Wrap one of the battery wires (positive red wire) through the centre and looped around and back through it to see if it helps.

https://uk.farnell.com/multicomp/33ri-20x10x10/ferrite-core-cylindrical-120-ohm/dp/9640398

Another thing to try is a big capacitor fitted directly across the battery supply. Any large capacitor with a rating of 50v or more would do. The controllers already have such capacitors in them, but maybe one is compromised in some way, so it can't filter properly.

Thank you for your advice but it is quite complicated for me to carry out.

 

[flecc]

Hi Flecc, what did you mean that "another one might not cure the problem." Do you think the controller on the older version of my Quando can wirk on my Quando. Thanks.

Your twelve year old is the same as older ones back to 1994, so that other controller should work. But I can't guarantee that it will work on both batteries since we still don't know what the fault is. It could be something about the management system in your wife's battery that is clashing with some of the controllers.
.

 

[hungrv1]

Hello, I open my controller ans see no burn inside as shown. The serial found is 9928-798-043. Can you advise me a replacement for this controller, please?

 

[hungrv1]

Your twelve year old is the same as older ones back to 1994, so that other controller should work. But I can't guarantee that it will work on both batteries since we still don't know what the fault is. It could be something about the management system in your wife's battery that is clashing with some of the controllers.
.

I agreed with you. But i sometimes used her battery when my battery run out. That is why we use only one charger since we can share battery each other. I check Ebay seller, they said their controller is only compatible with one has the same first 8 digits. Mine is different so can not buy. Should I contact direct Exee to ask for a replacement? or any source in Uk can help. The serial number found in my controller is 9928-798-043 whilethe Ebay selker requires 9824-1233-xxx. Thanks.

 

[flecc]

Hello, I open my controller ans see no burn inside as shown. The serial found is 9928-798-043. Can you advise me a replacement for this controller, please?

I don't know anything about the serial numbers on these, I only ever knew of one controller being issued as a replacement.

You could check with Ezee agents Greentech e-bikes on this link

If they don't have an answer they can check with Ezee Kinetics.

Or you could use this contact page direct to Ezee.
.

 

[hungrv1]

I don't know anything about the serial numbers on these, I only ever knew of one controller being issued as a replacement.

You could check with Ezee agents Greentech e-bikes on this link

If they don't have an answer they can check with Ezee Kinetics.

Or you could use this contact page direct to Ezee.
.

Hi Flecc,
I contacted Ezee and bought a new controller there. WW Ching responded very quick compared to greentechebike, still not got their resonse while payment done with WW Ching now. He's quick and flexible support. Thanks a lot for your valuable advice! Hope I get no trouble with replacement.

 

[flecc]

Hi Flecc,
I contacted Ezee and bought a new controller there. WW Ching responded very quick compared to greentechebike, still not got their resonse while payment done with WW Ching now. He's quick and flexible support. Thanks a lot for your valuable advice! Hope I get no trouble with replacement.

I don't think you'll have a problem, but if you do Wai Won Ching will look after you, he's a very nice chap. I met him and his son Ken back in July 2006 over another technical problem.
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