ECU/ABS fault C121D brake fluid preassure sensor (Outlander 08). How to fix?
 

So, got this fault which seems to be fairly common... ASC fault light in the display. I see there are several companies that offer repair service for this fault, but still fairly expensive. So does anyone know exactly what the fault or failing component is? I'm an electronics designer by profession and would prefer to try to fix it myself.

Had a failing ABS unit on my Audi A6 as well, and there I had to re-solder a broken bonding wire to the ceramic substrate... that was interesting with not the best equipment currently at hand when required.

Anyway, tips regarding this would be greatly appreciated!