ROBOROCK·FAULT ERR 21 WARN
Roborock Error 21 — Vertical bumper pressed
Severity: Warning — robot stops because something is pressing down on its LiDAR cover S6S7S8Q
DIRECT ANSWER
Error 21 means the vertical bumper is pressed — the spring-loaded cover over the LiDAR turret that detects when the robot wedges under furniture. Free the robot, make sure the cover moves, and retry.
#meaning · #causes · #fix — link straight to any section
COMMON CAUSES · RANKED
1
Robot wedged under low furniture MOST COMMON
Sofas and beds a few millimetres too low press the turret cover down and pin it there.
2
Object resting on the robot
A fallen curtain hem or a draped blanket is enough weight to hold the bumper pressed.
3
Debris jammed under the cover UNCOMMON
Grit in the gap around the turret cover keeps the switch closed after the obstacle is gone.
HOW TO FIX IT
No battery or electrical work involved in this fix.
Pull the robot out
Slide it out from under whatever it is wedged beneath.
Press and release the turret cover
It should travel down and spring straight back. Clear any grit from the gap if it sticks.
Restart, then fence off the spot
Retry the clean and add a no-go zone under the offending furniture in the app.
Did this fix your robot? No reports yet for this fix — be the first.
RELATED FIRMWARE
S7 series (S7, S7 MaxV)
SAMPLE DATA — dataset in progress4.1.2_07984.1.5_11964.3.5_16124.5.3_5936
Firmware timelines are rebuilt monthly from release notes. Versions marked as sample data are community-reported and not yet verified. Full firmware timeline →
Sources
Corrections
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