You have two options:
1) Amend your 2014 return to report the final K-1, write off any remaining investment in the S-Corp, and report a gain or loss on the dissolution.
See: "How do I Amend (Change or
Correct) a 2014 Return in TurboTax?"
2) Report the final K-1 on your 2015 tax return, with zero income, and write off the investment at a gain or loss in the current year. When you indicate a final K-1, TurboTax will ask you about the sale/disposition of your investment in order to report any gain or loss. You will need to know your basis in the investment in order to complete this section of the interview.
Schedule K-1 is entered under Business Income.
To find this section easily, follow the instructions below:
https://ttlc.intuit.com/replies/3301717