Just come back from a 200K trip, drove into my garage and nudged the end wall ( no damage fortunately) what had happened was the sensors were not working, funnily enough I now remember going through the last couple of toll booths and the side sensors were not bleeping. Have I accidentally turned them off, I cannot see any button with a "P" on it. I have gone round and given them a wipe to no avail. Is there a test I can do?