Car appreciation... the aesthetics, the engineering, etc

Is it diesel or petrol? If diesel the car might need a regen for it to work.

It's petrol. From the MB Forum:

"For what it’s worth, my GL63 (different car, same M157 power unit) hasn’t been used much lately - and mainly shorter trips too recently, but within minutes of heading out this morning it was doing it’s thing. That’s with the usual loads at this time of year - heated seats, climate control working away, entertainment stuff on etc.

Parked up after ~ 15 miles and restarted a couple of times during the day and it’s been stopping and starting as you would expect eg traffic lights etc or when queueing.

Mine’s a 2013, so a year or two older than yours, but I suspect it’s broadly similar in terms of the factors that enable stop/start to function.

Have never needed to put mine on charge either - not would I expect yours to need to be, especially after your 300 miles trip last week, a brand new battery from the dealer and a 40 mile run this morning."