Ok I am working a Mini Cooper 2009 Non S, with app. 88200 miles. Went to dealership with gear light on with exclamation point in center. Dealership replaced a " wiring harness" inside transmission and stated that was the problem. Week later same problem light came on went into limp mode, will not shift out of third. Cut car off and back on light is gone will come on about 5 minutes later after regular driving. Ran the CEL codes came back with a P2729. Researched and can't really find anything on that. Now have the light on and transmission in limp mode. Dealership said transmission needs replaced. Not agreeing with that. I keep reading about this light and many people are saying a lot of different things. My question is, is there any way to see what code is being thrown without taking it back to dealership to pay money. Obd2 will not read any codes. Only ones I had when I first got the car was p2729. U114e, u115e. And another one I can't remember at the moment. I erased them and am only getting the p2729 code now. Any one have any ideas about this.
And before you ask no the key isn't getting stuck in the hole like it does when this problem occurs.

 

I am not sure if this is the right thread if it isn't i will promptly move it to the correct one. The vin for the car is WMWMF33589TW74026