Hello,
I have a 13 cooper in my shop which came in for detailing. We washed the engine, then started the car, after cleaning the interior (for 5 hours, might I add: it was gross), this light came on and the car wont start...no starter clicks, no fuel pump, no external lights, no accessories, but radio. Though it was a dead battery, still nothing, checked the key fob battery, it's ok. We blew dry the engine, there was no indication of water in the ecu or fuses when we took the covers off.

 

I think that symbol is telling you a scheduled service is due (I could be wrong), look it up in the manual. Anyway, sounds like a bad battery. How old is it?

 

Assuming it's the stock battery, we dont have a tester, nor can see a date. We tried to jump it with no avail. So right now o disconnected the terminals and put a tender on it just to see if it is a problem.

Oddly, that image says "service brakes" in the manual. I cant imagine why brakes needing service would prevent the car from starting........

 

That icon could come on for a hundred things on a Mini. Same with the "1/2 power engine" symbol. It is generally cryptic and stupid.

I vote battery as well. FYI, if the positive terminal has a thing on it with a little red wire, it has the battery monitoring system, and if it is replaced it needs coded to the car.