If you programmed your new engine with a number that is already used in the base, the sensor will not up date the new engine. This can come up often when others run their engines on your layout. And, there is also a software switch to turn the feature on or off.
To Disable Legacy Base updates on ALL SensorTracks
Press CAB buttons ACC, 99, AUX1, 3
To Enable Legacy Base updates on ALL SensorTracks
Press CAB buttons ACC, 99, AUX1, 4