After you enter the sales tax on the car you get a screen with the heading "Major purchases results." The last line of that screen says "Deduction allowed" and shows the total amount of the sales tax on the car. But the wording is confusing. The amount it shows as "Deduction allowed" is not your total deduction. It's only the amount allowed for that major item. The total deduction for state sales tax on Schedule A line 5a in your tax return does include the amount from the IRS tables in addition to the tax on the car.
