How do I use the Section 179 deduction and bonus depreciation for a new van used for my business in Turbotax Self-employed 2017?

In order to claim Section 179 Depreciation on a new vehicle, you must choose Actual Expenses and not the Standard Mileage deduction.

To revise your answers, return to the business where you entered the vehicle and click Edit beside the vehicle you need to work on. Continue through the interview to the page "You've got a standard mileage deduction of $xxx".

1. Choose the option "Yes, I'd like to see if my actual expenses give me a bigger deduction."
2. Enter your actual expenses.
3. Indicate that you purchased it new.
4. Enter the amount you paid for the vehicle and the fair market value on the date you started using it for business.
5. On the page for Section 179 deduction, you will enter the amount you wish to claim (see screenshot below - click to enlarge). TurboTax will tell you the maximum amount available based on your business usage.
6. Check the box if you wish to take Special Depreciation as well as Section 179. This could increase your deduction, but may also affect your state depreciation.
7. Confirm that you wish to claim your actual expenses (which will be higher).
8. Continue to the end of the section to save your changes.

[revised 2/23/18 to add screenshot]

Well, I have gone through the interview and indicated that the vehicle was purchased new, entered the purchase price and any other expenses.  There has not been a section 179 deduction page come up or anyplace that I can elect to take that deduction or the Special Depreciation?!?

@musgrovewood Please see screenshot added to the answer above. This screen appears after you enter your vehicle's purchase price & FMV. However, this screen may not appear if you return to edit your prior entries.
If not, you will need to delete the vehicle and re-enter the information in order to claim the Sec 179 deduction.

Yes, that is what I needed to do. Thank you for the response!

well I use only forms.  how do you get this to work ? why does this need to be so obtuse  ?

to answer my own question, on the car and truck worksheet, fill out 32A, B and C with total purchase costs. then in 33 you can enter section 179 amount. Also check 35A yes and E 100%.... then it will work. Not hard, don't know why there has to be such a mystery about how to do this.

Also check actual expenses, fill out that section above as appropriate

I'm having the same problem as Musgrovewood on a 2019 sole proprietor return.  I have followed the steps you suggested.  I have deleted the vehicle and started over as was suggested in another reply but Turbo Tax will not offer the 179 deduction screen.  I have described the vehicle as a GMC HD 2500, selected "Truck over 6,000 pounds", indicated it was purchased new and another business vehicle was traded in, entered the trade difference and the total purchase price, business and total miles, insurance and interest expense, and elected to take actual expense rather than the mileage deduction.  Since the vehicle was purchased in mid-December there are minimal expenses.  Clearly the vehicle purchase qualifies for section 179 deduction.  Why won't Turbo Tax offer this option?

Maybe you just haven't gotten to the screen yet. I entered in my vehicle information and did not see the screen until later going through the turbo tax questions. The screen is under Business income and Expenses and in Blue bold at the top it says:

How much do you wnat to deduct for the business use of this vehicle?