Can you double-check that you didn't claim Section 179? Because if you did, that would explain what the program is doing. On your 2018 tax return, look at Form 4562. Section 179 should show up on Line 12 and column (i) of Line 26.
On another note, the $16,000 is the MAXIMUM deduction for the second year, which is based on a $50,000 vehicle. So a $35,000 vehicle will probably have less.
