Unlikely, the sensor is under windscreen cowl.
But might be worth mentioning to the garage that you only had the problem after the service, to see if they'll do you a good price. It's also very easy to change yourself if you get the part <5mins.
I'd get it done asap. The feedback (a judder) from the brake pedal on longer journeys got quite un-nerving but disappeared the moment I changed the sensor.
Thanks to all who have contributed to this thread and given the rest of us the heads-up when we get these issues.
Has anyone found out why this part is susceptable to failure after the car is left for a few weeksand not driven?
Is it because it is under pressure when parked but when running it gets varied pressure levels?
Is there something that can be done when you park up to ensure the sensor is left in a state that it won't get damaged?