Wednesday, March 19, 2025

An experience with XIAOMI Mi robot (Roborock) vacuum cleaner (model n. SDJQR02RR).



Xiaomi Mi vacuum cleaner

DISCLAIMER:

The information provided here is intended only to share a specific my own experience. Due to the serious risks to people and property involved in this type of activity, this information is in no way to be considered as a suggestion and/or an invitation to do the same.
This information can be incorrect, misleading and even dangerous.
Everything described here can lead to unexpected results.
I explicitly discourage anybody from repeating similar experiments.

Symptoms:

My cleaner stops working mid cleaning cycle. It goes in a OFF state. The only way to resuscitate it is connecting it to the charging station.
Once it comes back to life I can start a new cleaning cycle, but the cleaner stops again after few tens seconds.

Investigation:

I have managed to replace the 185 resettable fuse on the cleaner's mother board as per “Internet” suggestions: no change.

In order to further diagnose the problem I removed the battery pack from the unit and, after having carefully read the Safety Data Sheet for the product BRR-2P4S-5200S, I’ve removed the bottom (or top, depending from where you look at it) cover getting access to the internal BMS circuit board (the cover is glued, but with a little patience I managed to remove it with very little damage to the plastics).