On the covered eufy RoboVac L35, LR30 and LR20 series, Error 12 means the right wall sensor needs cleaning because it is covered in dust. First, clean the infrared sensor on the right side of the bumper with a dry, clean cloth.
Try in this order
0 of 7 completedWhat to do first
ReversibleClean the infrared sensor on the right side of the bumper with a dry, clean cloth.
Correct only the documented fault domain
Reversibleeufy's steps: eufy also says to make sure the RoboVac is on the latest firmware (V.2.2.0000 for these models), checked in the app by opening the Main cleaning page, tapping the Settings icon at the top right and choosing Firmware Update; factory reset by holding both buttons on top of the vacuum (start/pause and home) for 10 to 15 seconds, which returns the settings to default; and remove the dust collector and press the force shutdown button to see whether that clears it. If the steps do not resolve it, eufy says to contact eufy support and include a video showing the error.
Wipe the right-hand sensor
ReversibleEufy's first step is to clean the infrared sensor on the right side of the bumper with a dry, clean cloth. Dust on the sensor makes it read the wall wrongly and triggers error 12.
Check the bumper moves freely
ReversiblePress the bumper in with your hand and release it. It should spring back. A bumper held by hair or debris can confuse the sensors, so clear the gap around it.
Reset by holding both buttons
ReversibleEufy says to hold the start and pause button and the home button on top for ten to fifteen seconds. This is a factory reset and returns the settings to default, so you will need to set the schedule and maps again.
Remove the dust collector and force a shutdown
ReversibleAnother step is to take out the dust collector and press the force shutdown button, which can clear a stuck state. Refit the collector and restart.
Contact Eufy if it persists
ReversibleIf the error returns after cleaning and a reset, contact eufy support with the serial number and the model, such as the L35, LR30 or LR20.
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Exact questions
Common questions about “eufy RoboVac L35, LR30 and LR20 series showing Error 12”
What does Error 12 mean on a eufy RoboVac L35, LR30 and LR20 series?+
The right wall sensor needs cleaning because it is covered in dust.
How do I clean the sensor?+
Wipe the infrared sensor on the right side of the bumper with a dry cloth.
What does the factory reset do?+
It returns the settings to default, so you set the schedule again.
Which models does this cover?+
The L35, LR30 and LR20.