Programming a previous used 04-09 Prius Prox key will be more difficult then new oem, however please read helpful tips below to help

Toyota Prius (smart entry) trouble shooting tips and tricks.

1. Reset Smart ECU (T-code, MVP, Smart Pro) (all Keys Lost)
2. Erase smart multiple times before attempting. (add key)
3. Always check lock out switch, Located under the driver’s side dash.
4. Reset Smart ECU (T-code, MVP, Smart Pro)
5. Press Lock on original remote, then lock and unlock on new prox release and hit lock not unlock.(ADD Key)
6. Repeat register smart multiple times if process fails.
7. When inserting prox into slot do not allow key to fully lock into place. This allows the prox to be removed within the allowed time frame.

Insert Key Included