The best practice would be to dispose of the asset when you are no longer using it.
To do this in TurboTax,
- from the left menu, select Federal>
- Income & Expenses>
- Self-Employment Income & Expense click Revisit>
- Pick your business and click Edit>
- Scroll down to the expenses to Vehicle and click Edit
- On the Vehicle Summary, next to the vehicle, click Edit
- Check the box for I stopped using this vehicle in 2019
