check engine light on 2002 Hyundai Accent

Looking at buying a used 2002 Accent with 88,000 miles. a check of the check engine light being on showed a code of P0734, fourth gear ratio. proable cause, open or short circuit condition, Pressure solanoid faulty, internal transmission failure. The guy at Auto Zone said if the censor is on outside of transmission easy fix and to buy, but if inside transmission pass. Anyone know inside, outside and other opinions, thanks

2 answers
I concur; at our Hyundai dealership there is no rebuilding...or internal repairs.
forget about the guy from autozone. they are not techs.
i have a guy from hyandai who told me that any 700 code requires unit replacement. that is from the factory. dont know what the issues are but they are very emphatic about no trans work, just replacement.

Roy