This error actually refers to the Vehicle Worksheet that is used to calculate your vehicle mileage deduction. Apparently the numbers entered for the purchase price of your vehicle exceeds the limit.
You may wish to review your entries for your vehicle under Vehicle Expenses on the Business Expenses for your business. Work through the entire set of interview pages to be sure you answered the questions as accurately as possible.
If this doesn't remove the error on review, you may need to delete the vehicle and enter the information again.
The easiest way to find this section of TurboTax is to use the Search box at the top right side of the TurboTax header. Type in "vehicle expenses, self-employed business", hit Enter, then click on the "jump to vehicle expenses, self-employed business" link to go the Business Income & Expenses section.
On the Business Summary page, click "Edit" to the right of the business you wish to work on. Continue through the interview until you come to the Business Expenses screen. Click "Update" to the right of "Vehicle Expenses." Click "Edit" to the right of the vehicle you wish to review (or Delete to remove the vehicle).