Hyundai Repair: 1997 Hyundai Sonata 3.0 Tranmission Control Module, transmission control module tcm, transmission control module

Question
Car lurches radically between gears when accelerating. Also has problems going up STEEP hills when accelerating...can hardly make it over the top. I took it to a transmission shop for a diagnostic today, but they could not communicate with the transmission computer...it was dead. Engine computer worked find. How difficult would it be to replace this part myself? I'm told it is located under the radio? Do you know where I can find an online diagram showing this part? Any help is sure appreciated!

Answer
There's a problem with the diagnosis here.  If your transmission is shifting or attempting to shift, the transmission control module (TCM) is operating.  More likely, the scan tool the shop used caused the communication problem and not the TCM.  

Check your fluid level.  If okay, I'd recommend taking the car to the dealer for a more reliable diagnosis.