My 2020 Countryman (S, All4) is telling me it wants "brake pads." I've looked into the job and I'm thinking of doing it myself if I can find either a reasonably-priced scanner that can put the electronic parking brake in "service mode," or if someone knows the exact size of star socket needed to back it off by hand with the little motor removed.

What scanners do we like for these cars? I've never had one before, but if I can pick one up for a couple hundred bucks that will be genuinely useful (preferably for all my cars, too), then I might just do that. All of my cars have computers now...

Thanks in advance!

 

Are you sure you need a scan tool to do the brakes? Is it front or rear? You mention the electronic parking brake so I assume rear?
I just did the rear brakes on my 2021 Countryman but it is a base model not S All-4. On mine, the parking brake is an electric motor / solenoid but the brake calipers are normal hydraulic brakes. Your vehicle may be different but here's my experience.

It was (mostly) pretty easy to do the rear brake pads and didn't require a scan tool to put it into "service mode" to reset the brake pad warning. I went into service mode by holding the odometer reset button, then pressing the button on the end of the turn signal a certain way. The biggest thing here is to have the parking brake OFF (transmission in Park and chocked wheels) when trying to reset the brake pad warning. Otherwise it will say "Reset unsuccessful". Turning off the parking brake and trying again was successful for me. Change the pads first and put everything back together and put the Mini back on the ground with chocks before releasing the parking brake and trying to reset it.

Don't forget to unscrew the brake fluid reservoir cap and draw out with a turkey baster and save a few ounces of brake fluid before spinning back the pistons to make sure it doesn't spill over. Keep the reservoir cap off until done with both sides and top it back off with the fluid you removed or new fluid if needed.

I bought a Brake Piston Wind Back Tool on Amazon for $10. It worked but was challenging to figure out since I'd never used one before.
I was in AutoZone a couple days after that and remembered they loan tools like a brake tool kit with all sizes of piston plates to match most cars to wind back the piston. I wished I'd remembered to check out AutoZone for the tool but I keep buying one-time use tools and filling up my garage

 

I ended up getting the Bimmerlink app and their recommended OBDLink bluetooth-connected OBD scan tool. It looks like it will easily do the "service mode" thing, and also be an easier way to reset all my service minders than having to watch YouTube videos every time I change the oil and need to reset the mileage...

I saw some videos where they disconnect the parking brake drive motor and wind the little shaft back with a star socket. That looks easy enough. I suppose it would also work if you just used one of those caliper tools that turns the piston as it pushes it back. But the "parking brake service mode" seems like the way it's meant to be done, and since I'm saving hundreds of dollars by doing this project myself, I figured it's as good a time as any to just get a decent scanner that will be useful for other things as well.

But it's got me thinking... it would be kind of great if we could just reset the front caliper pistons that way, too... just a tap on your phone and... boom. They're off.