My Skoda Superb displayed an error message 3 days ago. The message was "Error ESP/ABS". The lights for ABS, Traction Control and Tyre Pressure Warning were lit up in orange on the dash.

 

Anybody got any ideas what this means?

7 hours ago, adoks10 said:

Anybody got any ideas what this means?

One, or more, of the wheel speed sensors has failed. Get a diagnostic scan done which will tell you which one.

Thanks PetrolDave,

 

I went to my mechanic today and he discovered that my left-hand rear wheel speed sensor is showing as faulty and needs to be replaced.

On 19/03/2024 at 08:36, adoks10 said:

I went to my mechanic today and he discovered that my left-hand rear wheel speed sensor is showing as faulty and needs to be replaced.

You cannot draw that conclusion based on a scan!

The scan only shows which sensor gives a bad signal, but that does not tell you the cause of the problem!

The cause can be:

1. Broken wiring
2. Broken (or oxidized) magnetic ring on the wheel bearing.
3. Broken sensor
4. Broken ABS/ESP module.
5. etc

First perform a proper diagnosis before randomly replacing parts!

 

The wheel bearing ring is not magnetic, it is castellated steel which interrupts the magnetic field produced from the magnet in the sensor, fracture of the magnet in the sensor is its usual failure mode and is invisible unless cut apart.

 

You possible cause 4 would not create a fault code for the wheel sensor, possible cause 5 is meaningless.

 

Possible cause 1 (the wiring) would create a different fault code, sensor wiring open circuit or shorted to ground.

 

On 20/03/2024 at 11:04, J.R. said:

The wheel bearing ring is not magnetic, it is castellated steel which interrupts the magnetic field produced from the magnet in the sensor, fracture of the magnet in the sensor is its usual failure mode and is invisible unless cut apart.

 

You possible cause 4 would not create a fault code for the wheel sensor, possible cause 5 is meaningless.

 

Possible cause 1 (the wiring) would create a different fault code, sensor wiring open circuit or shorted to ground.

 

Great explanation 👌