I got a 2018 Santa Fe AWD Ultimate 2.0T in March, and the tiptronic has never worked.
The most it does is when stopped you can force it into 2nd Gear. Once in 2nd you cannot put it in 1st.
When driving the tiptronic does nothing.
The dealer ordered a new tiptronic, and put it in but this did not fix the problem.
Has anyone else had this issue, and know what the real problem is?