I had the new tires put on and checked the pads and rotors and all looked good and the shop tire techs said all looked fine to them, stops straight but has had a check brake lining light on since I got it. Any ideas?
Sounds like someone did not replace the sensor the last time the pads were replaced. It's one of 4 or maybe more. You'd have to pull out the sensor and see if it has been compromised or not.
First thing I would check is the level of the master cylinder. As pads wear the fluid level drops & that can make that light come on. Also the fluid should be changed every 2 years in a MINI. More often if you plan to hit the track. If the light has been on since you got the car then what Nathan says makes sense.
The tire techs. at the tire dealer told me what more than likely caused the light was brake dust as the new Cadilac's also suffer from the same problem.
In the years I've been playing with MINIs I've never seen anyone report that brake dust buildup has caused the light to come on. The sensors are in the pad, when the pad gets worn to the point that the face of the sensor is exposed to the brake rotor the face of the sensor is removed by the rotor, this breaks the electrical connection causing the light to come on. Unless there is some malfunction someplace that is the only way the light comes on. If your light is still on I would check each sensor to make sure the face of the sensor has not been worn away.
Guys with Caddy brake experience should not be messing with your MINI brakes. Like Nathan said brake dust doesn't make the light come on.