Hyundai Repair: code P0711, sante fe, fluid temperature

Question
I drive a 2001 Sante Fe.  My car just started jerking when idling and going up
hills.  My check engine light is not on.  I've recently had an oil change, new
brake pads and a transmission flush.  My service guy ran a diagnostic on it
and got the response of P0711-trans fluid temp sensor A.  However, he does
not do transmission repairs and was not able to tell mew much about this
code.
What does this mean?  As a woman i am wary of being taken advantage of.  Is
this a problem that should be address immediately?

Answer
The definition of the code you give is correct, it's a problem with the transmission fluid temperature sensor readings.  But this shouldn't cause a problem when idling.  It may cause some abnormal shifts, however.

As long as the transmission is shifting normally, it's probably not necessary to address the transmission temperature sensor immediately.  The jerking, on the other hand, could be significant.  Since it occurs at idle, I'd expect it's some sort of engine performance issue, and that could get worse if left unrepaired.  If the condition is reproduceable, I'd recommend having the vehicle checked by a good driveability technician.  A good driveability technician should be able to tell something about the nature of the problem if he can feel it and discern what makes it change and how.