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mnh-jansson / open-battery-information

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BL1850B LOCKED? #16

Open a9566847 opened 3 months ago

a9566847 commented 3 months ago

Replace and check that the voltage of each battery string is normal...the fuse is also normal! But it cannot be charged...can it be released? 001 002

MeatEasterPearls commented 2 months ago

Can you open the battery and check which microcontroller it uses? Maybe just open it up, take pictures and post them here.

a9566847 commented 2 months ago

P_20240912_192158

a9566847 commented 2 months ago

The lock status value is 3, the so-called strikeout?

MeatEasterPearls commented 2 months ago

The microcontroller is a STM32L, which is good. You should be able to unlock it. What happens when you press "clear errors"?

mnh-jansson commented 2 months ago

I've discussed this over email with Joe and i suspect it is locked due to the battery message being locked. In its current state, the reset battery message is broken. It's actually good that it is broken because it would do more harm if it would work at this time. I have a solution for this but i have not yet had time to implement it. All time has gone towards F0513 unlock.

Some more details about the battery message. The battery message is the original implementation of the Makita communication protocol and is common through all battery revisions. The earliest batteries were locked by the charger by setting a certain nibble to a non-zero value. This had to be implemented in all the newer batteries so that the charger could be compatible, but the additional commands vary between the newer batteries. The BTC04 even struggles with F0513 and STM/MAK/RAJ and detecting what commands are supported and uses bruteforce to just test and conclude depending on answers. I do the same here. In newer batteries the battery itself has some control of the lock nibble, but the original implementation seems to be present still and can disallow the charger to continue. This is usually the case if the LED indicator on the battery shows no error, but the charger does.

As to if this is related to the "3 strikes and you are out" rumor, no it is not.

Y13Lab commented 5 days ago

What BMS microcircuit is used on boards with STM32 ?

a9566847 commented 4 days ago

STM32 has integrated BMS circuit