" Mysterious warning lamp failure"

For some time ago, when I  changed the battery in my Octavia 2007 2.0 tdi,  a number of error indications occured. All  of them disappeared after a short time, but the Esp warning light continued to lit. It was performed a diagnosis test as concluded with a defective brake pressure sensor. I visited today  the dealer to replace the sensor. They stated then that the sensor was ok, and performed a new diagnosis , and this concluded again with the same error;  A  defective brake pressure sensor . 

 

They suggested extensive testing of the electrical system as the next step..

 

Some who have heard of similar cases ? What can this be due to? 

 

Best regards