I'm new to this forum and I've been searching for hours but have not found exactly the issue mi mini is presenting, if there is a topic covering my question I apologize in advance and will be thankful if you can direct me to that post.
I recently purchased a mini 2012 R56s with 25k miles from a bmw dealer, they told me the car went through thorough inspections and it was in good shape, I don't know much about cars but I checked the basic stuff and it seemed ok. Now after a couple of weeks it started to give me problems.
First the coolant level, I was driving on a highway and the car gave me an overheat alert so I stopped to check and found that the coolant reservoir was completely empty so I got coolant and top it then continue driving, when I got home I checked again the level and it was 1/3 down. At that point I had not used de A/C for over 5 days but I decided to turn it on since it was a warm day only to discover it only blowing hot air even when the temp was set to the minimum, this air immediately felt like it was coming directly from the engine not like when you set your car to warm up for cold weather season. Also, I found that the A/C kind of works when cold starting the car, it blows cold air but not as cold as it should be, however, after 2 minutes of driving the car it will start blowing super warm air again.

Going back to the coolant issue, I checked for leaks but did not find any nor on the floor or the parts around the coolant reservoir, I even put some plastic below the car for a couple of days to make sure it was not evaporating but did not find anything.

I am taking my mini back to the dealer next week, they said they will cover the repairs and everything but I want to make sure they replace all the pieces needed and fix the car for good so I am looking for advice as to what could be causing these problems. Do you think these are two separate issues or one is consequence from the other?

Thanks!

 

Please keep us updated.

Mine had a coolant leak from the expansion tank (hairline on one of the return hoses) and then one of the clamps was failing on a hose from under the thermostat housing (the one that is hard to put on when changing said housing and is almost not long enough).

My AC stopped working as well and now just makes like a "hollow noise" from the vents. It was working fine prior.

 

A cracked and leaking (plastic, of all things!) thermostat/housing assembly can leak and not leave any evidence on the ground. Mine was leaking onto the top of the bellhousing and burning off or evaporating before hitting the ground, a common issue. I just replaced my t-stat/housing assembly and the coolant transfer pipe (also plastic!) between that housing and the rear of the water pump area myself. Not an easy job, but I saved a ton of cash by not having the dealer or an independent shop fix it. As far as the A/C goes, could be related, as the ECM may command the A/C off if there is a low coolant level or over-temp issue. I hope that your BMW dealer takes care of you. Let us know how it all goes.