Help with Fault Code B211A

[kev159]

I have a 2020 A-Class W177 200D. I have a problem with the B211A fault code. I don't know where to go to solve my problem. Do you think Xentry can help me clarify this issue?
The only issue I have is the left rear obstacle sensor which beeps continuously when reversing even when there are no obstacles nearby.
Has anyone else encountered this problem?

 

[osaman1999]

First of all, you need to check the sensor. If it works fine, try replacing it with another sensor in another place in the car and check if the problem persists with the same sensor.

 

[cmkfarooque]

Simply disconnect the sensor connector and check if the beeps are heard. If not, clean the connector and reconnect it. If the problem occurs again after reconnecting the connector, replace the sensor with a new one.

 

[mustafa666]

Clean the sensor itself thoroughly. I had this problem on a C-Class car and it was caused by debris buildup on the surface.