Changing business use car to a different car

[global77]

I have a car that was listed for business use and am in its third years of depreciation. What happens if I were to replace that with a new car at the start of the fourth year, while the previous car will be changed for personal use only?

How do I inform the IRS and what do I enter when I come to the car expenses and deduction section when filing my tax?

Thank you.

[Anonymous_]

See https://bradfordtaxinstitute.com/Content/onvert-Business-Property.aspx