The Xiaomi m365 electric scooter is driving, but it has no power.

Hello. I have such a problem with the scooter that there is no power. I ruled out all causes and found out the battery was probably to blame. The battery is as much as it should have, i.e. 42 V, but I suppose it does not have the right amperage. The cells are new I suppose something is wrong with bms. And here I have a question, is it possible for bms to somehow steal amps? The scooter shows no errors, the bms is blinking blue, the controller is working. The scooter is on, but it has no power.

robi239 wrote:

The battery is as much as it should have, i.e. 42 V

Measure the voltage under load, maybe the battery is already worn out, it has a large internal resistance, and the voltage drops under load.

The battery is brand new, but I will try to check it under load.

robi239 wrote:

The battery is brand new, but I will try to check it under load.

And this scooter doesn't have an economy / sports mode switch or similar?

Yes it is, but I'm talking about the normal mode. I forgot to write that the engine is running erratically and there is no power. Of course, the engine is good.

robi239 wrote:

Yes it is, but I'm talking about normal mode. I forgot to write that the engine is running erratically and there is no power. Of course, the engine is good.

If the motor jerked in any of the modes, it could mean that the battery protection circuit is shutting it down periodically due to a current limitation which may have "gone down" somehow.
The engine control unit may also be faulty.

When I turn the engine on at low speeds, it runs evenly, but when the throttle is at full speed, it jerks it.

Added after 5 [minutes]:

I suspect that it is the battery driver called bms on that takes care of charging individual cells. But if there is something wrong with it, the red LED is on and I do not know if it has the power to block the voltage or current of the product coming out of the battery. This is what it looks like

I think I have already found the cause, someone made a short circuit and the elements in the photo were burnt and in their place are soldered tin. Pictures are from good item. Please describe these items and where I can get them. To be precise, element F2 is a fuse and it is not replaced with tin, but it is sooty. [img-1]

Hello, how do you know that the m365 scooter has errors, or what color should the controller and battery shine on, if everything is ok?

If there is anything wrong, the scooter squeals and the taillight flashes. The bms on the battery should flash blue, the controller - the red diode.

does, could you please contact me? I have the same problem with the scooter and I don't know how to fix it.

Hello, I sent my driver to a guest from the vicinity of Krakow and I had to re-program it with the display and everything is flawless today, you want to send you the information for the guest on the priva what he does scooters

Hey thanks since then i've learned a bit and i also program drivers. Thanks greetings

I join the topic. Sudden (overnight) loss of power, accelerates slowly, up to max. 19 km / h (it was 24). No load (wheel in the air) 21. Mileage 1100km, I thought the battery was> 41V (according to the app) and when driving (consumption 330W / 8.4A) it drops to 39.3V so also without a tragedy.
Hence, I thought that the shifter did not work (the effect as if I had not fully driven). A new one came, I changed it and then the same.

And now I don't have much of an idea. I measured the motor - all 3 phases very low resistance (about 0.1R), after spinning the wheel by hand on each phase it induces to about 6V, after shorting any two phases, the wheel brakes identically. So the engine looks OK, what else can it be? Controller (the one with power circuits in a plexiglass housing)? Oh, battery temperature 31 * (as much as the surroundings, I was already driving at 44 outside and it was OK).

greetings

Hello. I bet on the controller and more precisely mosffet transistors.

From the power side, you can check the uniformity of charge of each of the 10 sections of the battery in the application. Or take a voltmeter.
Max. the permissible difference is 0.2-0.3V, above this value, it is worth stretching an inch section and checking the condition of each of the cells.
The damaged section can also give the effect of "low power", because the BMS finds too much voltage drop and automatically lowers the power consumption (as a last resort, the scooter switches to ECO mode).

I got a new controller, unfortunately it's not identical. Low power connectors (the 3 in a row) are slightly different - the plugs fit "forcefully" but do not snap shut. The scooter can be turned on with the button, but it can not be turned off or drive. The rear light flashes 1x approx. Every 2 seconds. The controller board is slightly different (like a revision) but overall looks OK. Before I send back to the seller, maybe you have some ideas? Maybe the firmware is from a different model? I can't find anything on the network for this flashing. The app ("m365 Tools") connects but shows no data.
PS. I measured the mosfets - no short circuits, the rest of the engine would not work smoothly if something was wrong on one of them.

I ordered another controller, this time a drug and the problem is solved. I had to get fired sooner. Watch out for these 3 low-power white connectors, from what I can see most of the offers have slightly different ones. It can be postponed, but an extra job. I managed to buy the original ones.

kangyooni wrote:

I join the topic. Sudden (overnight) loss of power, accelerates slowly, up to max. 19 km / h (it was 24). No load (wheel in the air) 21. Mileage 1100km, I thought the battery was> 41V (according to the app) and when driving (consumption 330W / 8.4A) it drops to 39.3V so also without a tragedy.
Hence, I thought that the shifter did not work (the effect as if I had not fully driven). A new one came, I changed it and then the same.

And now I don't have much of an idea. I measured the motor - all 3 phases very low resistance (about 0.1R), after spinning the wheel by hand on each phase it induces to about 6V, after shorting any two phases, the wheel brakes identically. So the engine looks OK, what else can it be? Controller (the one with power circuits in a plexiglass housing)? Oh, battery temperature 31 * (as much as the surroundings, I was already driving at 44 outside and it was OK).

greetings

And the hall sensors are ok?

Colleagues, before you start disassembling your hardware, I suggest you check the DRV software version.
Explanation: the newly introduced KRD regulations oblige scooter manufacturers to program controllers to work at a maximum speed of 20 km / h.
The uncritical confirmation of the question about the software update by the Xiaomi application ends with loading the control software with this limitation.

Solution: upload an older soft, e.g. DRV 143 (m365, PRO) or 233 (pro2, es1, etc.)

Added after 6 [minutes]:

kangyooni wrote:

I got a new controller, unfortunately it's not identical. Low power connectors (the 3 in a row) are slightly different - the plugs fit "forcefully" but do not snap shut.

Buddy, I think you bought the "XiaoSimilar" driver .. The original PCB color is always deep navy blue and there is a white sticker with serial number on the transparent cover. This principle works with any version of the driver, 1-3.
I would also like to add that the drivers on STP mosfets had the highest performance after tuning the software
There are also fake controllers that cannot even be updated by software.

It's been two years since I replaced the controller board with MOSFET transistors and again the problem. Low power, the lamp flickers unevenly after switching on and then (with the lamp switched off there is no such thing) the engine also runs unevenly, "shoots" a bit like a two-stroke at idle. Lamp replaced - no changes. I would also bet on the controller but strange thing, I wanted to be sure. Additionally, it's getting harder and harder to buy it locally, has someone from Aliexpress taken? Worth it? Dark blue laminate, but you never know what they will actually send.

To check that the 5V line is not sticking anywhere. If not, check the polymer fuse in DRV - F2.

Buddy, the symptom is quite characteristic - remove the controller, remove the transparent cover, in the lower left corner of the plate, find the green element labeled F2.

It would have to be replaced (it loses its properties over time), but if you solder a 0.1mm wire jumper there, it will also work and will probably not damage anything

Thanks a lot! I will try only in two weeks, let me know if it helped.

Pontikos wrote:

Buddy, the symptom is quite characteristic - remove the controller, remove the transparent cover, in the lower left corner of the plate, find the green element labeled F2.

It would have to be replaced (it loses its properties over time), but if you solder a 0.1mm wire jumper there, it will also work and will probably not damage anything

On what do you base your observation that F2 loses its properties over time? I am asking out of curiosity, because I have similar symptoms, this fuse is hmm .. rather difficult to get. And I am surprised by the proposals to replace it with a wire. I would rather suspect that when too much current flows, this fuse "creates resistance". After the current drops, it has little resistance again. Thanks to this, you do not have to constantly dismantle the platform.

keseszel wrote:

On what do you base your observation that F2 loses its properties over time? I am asking out of curiosity, because I have similar symptoms, this fuse is hmm .. rather difficult to get. And I am surprised by the proposals to replace it with a wire. I would rather suspect that when too much current flows, this fuse "creates resistance". After the current drops, it has little resistance again. Thanks to this, you do not have to constantly dismantle the platform.

It is very good that you paid attention to this. I put in an ordinary 500mA smd fuse.
In fact, the original polymer fuse loses its properties. Its maximum forward current drops.
Unfortunately, this phenomenon occurs in many devices equipped with such fuses. I used to repair the autoboss v30 diagnostic tool. Same situation.

Pontikos wrote:

Buddy, the symptom is quite characteristic - remove the controller, remove the transparent cover, in the lower left corner of the plate, find the green element labeled F2.

Thanks, it helped right away. I soldered a jumper made of a thin wire.
Unfortunately, the kick is still no longer there, but it is already 4 years old and has driven 1500 km. However, it works evenly and is suitable for jumping to the store. Thanks!

kangyooni wrote:

Unfortunately, the kick is still no longer there, but it is already 4 years old and has traveled 1500km. However, it works evenly and is suitable for jumping to the store. Thanks!

For a mileage of 1500km, it's too early for anything to happen to the battery or anything else.
First, check for voltage drops when accelerating.
You wrote that you replaced the driver, the mileage is in it. How many km did you have on the old driver?
Are all your bearings in good condition? I had one such art in which there were practically no bearings on the motor. He was spinning hard and mega loud.
The guy just came to the service when he burned the tracks in the controller and the transistors ...

kangyooni wrote:

Pontikos wrote:

Buddy, the symptom is quite characteristic - remove the controller, remove the transparent cover, in the lower left corner of the plate, find the green element labeled F2.

Thanks, it helped right away. I soldered a jumper made of a thin wire.
Unfortunately, the kick is still no longer there, but it is already 4 years old and has traveled 1500km. However, it works evenly and is suitable for jumping to the store. Thanks!

Should I also have to be interested in him? This F2 .. Mine also has similar symptoms, I was also tired of them here. I ended up driving with an extra lamp.

The speed I got on the scooter. And here zonk .. The speed was after ... the jump when the wheel broke off the ground.
Holding the front wheel up for a few minutes, the counter showed the distance traveled a few hundred meters more. And another curiosity - the maximum speed that he later indicated was about 27 km / h. When the scooter was standing and the wheel was raised.

keseszel wrote:

Should I also have to be interested in him? This F2 .. Mine also has similar symptoms, I was also tired of them here. I ended up driving with an extra lamp.

Replace the fuse F2 and after the problem. After inserting the jumper at the smallest overload of the 5V converter, it becomes dead.

As for the engine speed, it is unstable if the engine is not loaded (only at higher engine revolutions).
The PID controller is often unable to maintain the set speed and in the application you may see the wrong or unstable speed.

If you have damaged F2, it also affects the voltage of the hall sensors in the engine. If it is unstable or much lower than recommended, the max speed will be lower.