Bosch powerpack BMS, value for a missing resistor

Joined
Jan 18, 2025
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2
Location
France
Hi guys,
First post but Not my first problem with the bosch system...

I had this strange idea to repaint my powerpack because it was slightly scratched (about 5000km old),
I used a bit too much strength and a screw driver to pry open it...
As a result, I ripped off a resistor from the board , since then the battery has a default ( excessive balancing current according to bosh software ) and switches off after 5sec... and my paint job is awful.

Could some one with a bms in his shop would be nice enough to measure and give me the value of this resistor ?
according to the datasheet it's connected between VC0 and VSS pin 20 and 21 on the ISL94212, the data doesn't give any value for it.

Any help would be great!
Thanks
PS:
I attached a pic of the position of the missing component.
By the way it's a powerpack 400 for a gen3 system.
 

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If it's a resistor (typically black with the value number printed on it), it's probably a pullup for a signal, and would be the same value as other pullups on other signals around it.

If it's a capacitor (typically brown, no markings) it's probably a filter capacitor and would be the same value as those around it on the same voltage bus. But if it's instead something like part of an RC filter, the wrong value gives the wrong time constant.
 
Thanks for the clues, unfortunately there are no similar resistor around....
The marking is impossible to recognize on the destroyed component.

I don't want yet to mess around trying different values... not to burn my house down!

Thanks again, I will continue my quest for information until I get bored and try to play around with some solder (keeping an extinguisher around)
 
Is it on a signal line that requires a pullup (or pulldown) resistor?

Is it on a power line that requires a filter cap?

If you have the bits of the part, take pictures of the pieces in direct sunlight so your camera can pre-focus on them before you snap the shutter, and don't hold the camera in hand, use a holder and use the timer function so your touch doesn't shake it. You can get very sharp close up images doing this, and possibly use the images to reassemble the part virtually and figure out what the marking was. Or post them here so someone can help with that.

It'd be uncommon for the part to be different from the others used for the same purpose all around that MCU.
 
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