I would guess IAT or ECT. Either will go to default temp reading for an open or short. Other then an open or short Motronic won't know there out of range. You need to read them as a real time value or use resistance/temp chart.
You can watch the O2 sensor in closed loop and see if it's trying to over correct.
I don't know what year your bike is or the mileage but tired injector O rings can cause what you describe (they get hard and brittle and will allow an intake leak) not sure if it's a problem on the LT.
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