I have had problems for a long time with a number of error messages appearing on the screen. After some searching on the web and an OBD scan, I have concluded that it is the ABS sensor on the left side at the rear that is causing the problem. The error message I got was this:
 

C101C07 - Passive/Abiogenesis. Left rear ABS wheel speed sensor - Mechanical malfunction
 

I then replaced the sensor myself with this one, which came up when I searched on my car reg.no. at T. Hansen: https://www.thansen.no/bil/bildeler/abs-sensor/sensor-abs/n185661/pn1038144 

The part looks the same in appearance and it went well to install. Unfortunately, all the error messages appeared on the screen again and I did another OBD scan and I got a new error.:
 

C101C4A - Left rear ABS wheel speed sensor incorrect component installed
 

Did I simply get a wrong part or do I have to tell the car somehow that it got a new part? What do you advise me to do? It would be nice to get rid of this problem.

IIRC there are 2 versions of the rear wheel sensors depending on whether the vehicle has park assist.

 

Mechanical malfunction sounds like there could be a problem with the magnetic ring that the wheel speed sensor uses?

11 hours ago, PetrolDave said:

IIRC there are 2 versions of the rear wheel sensors depending on whether the vehicle has park assist.

 

Mechanical malfunction sounds like there could be a problem with the magnetic ring that the wheel speed sensor uses?

Thank you. I will try that to find the other sensor. It is not park assist on my Octavia.

@PetrolDave I bought a new one, not for park assist as you suggested. My car does not have park assist. It worked well. All error messages disappeared. Thanks a lot.