Vehicle sale calculating entire sale price as gain

[PCF]

I used a new vehicle for a small percentage of its mileage for my rental property, so I took the standard mileage deduction.  I have now sold the vehicle (traded it in) and TurboTax is calculating the entire sale price as a gain:

Business portion of purchase price        1,703

Depreciation portion of mileage                215

Adjusted Basis                                            1,488

Business portion of sale price                    597

Loss                                                                 891

TurboTax says my gain was 597.  I calculate a loss of 891.  Can anyone explain this?

Thanks!