My Roborock S6 suddenly stopped charging. No LED on the dock, no life signs. Naturally, first thought: power brick or cable. But those were fine, the issue was inside the dock itself.
After cracking it open (carefully, because some capacitors in there can still hold a decent charge and will happily zap you if you short them), I found the culprit: a dead Schottky diode — or as I like to call it, “that black heat-sinked little thing that died quietly and without any warning, leaving me to vacuum manually for a week”.
The part in question was an MBR5150 which of course I couldn't find locally. I ended up sourcing it from Mouser:
Panjit MBR5150_R2_00001
There is also an replacement part, if you can't find the MBR5150, MCC SR5150.
Good news:
You don’t need to remove the heatsink to replace it. If you have a decent solder pump and a pair of small snipping cutters, you can desolder it cleanly in place. Just take your time, the heatsink draws a lot of heat.
After swapping the diode, the LED came back to life, and the Roborock started charging again like nothing ever happened.
So if your dock is dead, no light, no charging, check that MBR5150. It’s a small fix(0,55 € + shipping) that saves you from buying an entirely new base.
