le baron 91 Electronic transaxle giving fake overheating
 

Hello my Lebaron 91 with 4-speed Electronic transaxle shows overheating transmission while scanning the TCM. However the real transmission fluid hose temperature seem to be OK when I grip on it at the radiator tank. Is it so that the transmission fluid temperature on the y604 transaxle is calculated and not actually measured? This is really a problem because the TCM changes the gear-pattern due to "overheating" making the car very unpleasant to drive (increased rev an hard shifting) arter 45 minutes Driving.
I think my transaxle is actually ok due to it is renovated and this is a sensor thing. How do I find the cause and fix it?