Rear end bump now showing brake sensor fault

[Packrat]

Hi all

I. Have a 2004 s60 t5 which was faultless until the wife backed it into a post.the. Damage is minimal apart from a little crack in the bumpers corner edge.but since this incident the car is showing a brake sensor fault.could this be related or just a coisidence? ..car seems to be braking fine..I don't really fancy paying a dealer for a diagnostic if it can be avoided..

Thank you for any help