Never had that problem. I did have a sensor problem, an "anti-knock" sensor that went bad, but it was a no-cost warranty repair that took all of 15 minutes when I took it to the Sprinter dealer with an appointment.
Unless you have a Mercedes Benz OBDII code decoder, that P0544 might not actually be an exhaust gas temperature sensor. Remember that your Sprinter was built in Dusseldorf, and the codes may mean something different than if it was built in Detroit. I don't know for sure; the point is, don't assume.
Any recurring "nuisance" warning light is indicative of something wrong. The code itself is not a problem; whatever caused the code is the problem. The more often you reset the code instead of fixing the problem, the more likely it is that you'll have a bigger and more expensive problem to fix later after you've made it worse by not fixing it when it was still a small problem.
Engineering: Finding complex solutions to simple problems you didn't even know you had.