Not helpful

[Mike9241]

it should but you must enter total mileage and business mileage without these two numbers Turbotac computes usage as zero thus no depreciation. 

[KrisD15]

You need to go through the Business section and enter the vehicle expenses first. 

Depreciation should be calculated after you enter your expenses and mileage so the program knows the vehicle was used for more that 50% business.