BMW E90 overheat warning

[MyMercedes46!!]

I have a 2012 E90 with N52 that gives emergency overheat warning and goes into limp mode. I stop the car and open the hood and shoot the head with my infrared thermometer. Normal temp always--193*F__201*F__etc. ECT sensor on the front of the head has correct ohms resistance. No codes in ECM/DME. Realtime data shows coolant pump RPM as 234 at all times. Pump and thermostat are new. I think that my ECM is trashed. Anybody else have false overheat alarms?