Bypass Lock Mavic Pro Battery without SMB Flasher

[O'Neill]

Hi, I hope this is useful So one of my mavic pro batteries locked due to an accidental error when I was about to balance charging. I don't own a Texas Instrument (SMB Flasher/Battery Flasher I call it), and a repair shop I know has this hundreds of miles away. So I tried to connect the battery without BMS, and it did, but with the error message "battery signal error", so I think what battery signal means here is the path to send and receive battery data from the BMS so that the Mavic can work with the smart battery. The good thing that I found is that it is locked but the battery is still working, it's just that there is a block blocking the flow to the mosfet. So we just need to jump the tide in there. And as you can see in the photo how I did it and it worked fine and have done a flight test in such conditions, everything is normal, no problems with the battery voltage or temperature readings, no problems with the accuracy of the RTH timing and battery percentage, no problem. In fact I get an increase of about 2 to 4 extra minutes of flight time! I assume this can happen because the mavic pro's internal BMS system has cut the amperage distributed by the mavic pro fleet, so you won't get a pure 3830mAh after going through BMS, but apparently this way the real capacity of the battery cells is actually read by the mavic pro and with By itself the flight time increased, so I tried it with another battery and found 27 minutes of flight time! At least this method can help in times of emergency if you doubt the long-term effects. But I hope it will be fine for a long time. And if you ask what the second switch is for then it is to boot the fleet, this switch prevents the Mavic Pro from booting immediately once the battery is inserted, all we need to do is turn on the battery from the original button then insert the battery then the second switch is turned on. As I said above that we can turn on the Mavic Pro without BMS but will receive an error message, in this way we have succeeded in eliminating and bypassing the lock system on the Mavic Pro battery. I think this will also work on other dji fleet batteries.. Do it at your own risk.

 

[radenrezky]

bro, i think it's not good idea for your quad copter safety and can damage the other circuit inside the quad copter side because BMS itself can act as a balancer from each batteries ( 3 batteries output become one current and voltage controlled supply to main board). This can lead the possibility to fry the main circuit also, because LiPo battery cell's quality at sometimes will degrade during use (or flight) and this is what the BMS do to protect your quad copter from crazy cell's..

 

[quaddamage]

For flashing Texas Instruments BMS chip:
You don't need the TI programmer, there is free software to unlock the battery even with 3$ SMBus dongle.
(I didn't tried that yet, but I plan to)

For bypassing the MOSFETs:
I am surprised it worked, most DJI drones will refuse to arm motors when battery status is abnormal. Is Mavic Pro allowing to start motors in such case out of the box, or does it require some parameter changes?

For the increased flight time you currently have:
I assume low battery notification still works in the same way, so this means the reason for the time increase is that you're charging them more. I guess DJI went safe with how much charge the BMS chip allows the cells to take (assuming you're not overcharging them). Anyway, with BMS in "permanent fail" mode, balancer is disabled.

 

[radenrezky]

For flashing Texas Instruments BMS chip:
You don't need the TI programmer, there is free software to unlock the battery even with 3$ SMBus dongle.
(I didn't tried that yet, but I plan to)

For bypassing the MOSFETs:
I am surprised it worked, most DJI drones will refuse to arm motors when battery status is abnormal. Is Mavic Pro allowing to start motors in such case out of the box, or does it require some parameter changes?

For the increased flight time you currently have:
I assume low battery notification still works in the same way, so this means the reason for the time increase is that you're charging them more. I guess DJI went safe with how much charge the BMS chip allows the cells to take (assuming you're not overcharging them). Anyway, with BMS in "permanent fail" mode, balancer is disabled.

may i have the link for the software, capt? i need to solve the riddle of my Mavic 2 Zoom BMS battery.. it's been months i seek the answer to do this. i can do with my old M1P (for private use, no cell mods) but since bought M2Z, it's hard enough for me LoL

 

[quaddamage]

may i have the link for the software, capt

It's explained here:

About reviving a Mavic Pro battery

I’ve searched and I haven’t found anything so I suppose there’s not topic talking about this, but I suppose that this is something common, so I need to try it. I’ve a Mavic Pro with two batteries, I use to take a lot of care of all my equipment, but I didn’t follow everyone recommendations and...

mavicpilots.com

 

[quaddamage]

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