You’ll have to set up the payroll item for your employee's Personal use of a company vehicle as follows. The amount shows up on his w-2 in Box 14 as a fringe.
Before entering the said item for your employee, there are a set of payroll items you need to use depending on your situation.
You can visit this link for instructions and detailed steps: Personal Use of Company Car (PUCC). It will show you how to set up and report PUCC on the employee's paycheck.
And, it's correct that the amount will show up on the W-2, box 14 with “PUCC (CAR)”. This is also reported on the 940 form box 3. Please refer to this article: Supported pay types and deductions explained, then find Personal use of company car (PUCC) to know how the item is reported on your federal forms.
If it's not reported on the 940 forms, I recommend contacting our QuickBooks Desktop Payroll Team. They can help correct your payroll and ensure you have accurate returns on your payroll forms.