This is a simple one, but actually one of the primary reasons I bought the Launch scanner. Unlike every other German car I've owned (BMW, Porsche, Audi) there is no way to change just the temperature unit from °F to °C (which I prefer). The setting exposed in COMMAND is either all metric or all customary US units. All metric won't work for me since all our roads are signed in MPH and miles. Launch scanner makes this possible:

463.261 - G550So far, so good. I was expecting to see somewhere in COMMAND a software glitch due to having US units set but also "Degree C" set causing some invalid state, but all my temps are correctly displayed throughout the system in °C. I'll update this thread if I encounter anything weird.

Fully expect this is of limited use to most, but perhaps there is some future poor soul who longs for °C in a US Mercedes-Benz and stumbles upon this in a search.

Hat tip to @streborx whose thread format I've followed for this post. I find it really easily to read and it would be nice to have some consistency as the knowledge is built up here.