I had a check engine light come on over the weekend with the above codes read by my Automatic dongle.

My 2012 R56 is out of warranty (51k miles), but I may take it back to the dealer anyway since I think they've previously replaced the thermostat and other sensors under a "campaign" and this may be a related issue.

Opinions and recommendations are welcome.

 

I think you already have the right idea. All of those codes point to the thermostat..

 

looks like Coolant temp sensor.



P0116 - Coolant Temperature Sensor rationality Check
P0118 - Engine Coolant Temperature Circuit High
P0128 - Coolant Thermostat (Coolant Temperature Below Thermostat Regulation Temperature)

Check the date and mileage when anything was replaced, and what the warranty period on the replaced items is.

 

Thanks to all who responded. I figured I had a fighting chance to get the repair done for free at the dealer since the thermostat was replaced in 2013 (even though I'm out of warranty). Agreed to pay a $50 deductible (which would have applied had I bought the extended warranty). Hopefully they've gotten the bugs worked out for this part. It's actually my third thermostat in 3 years!