Yes, TurboTax implements the Deduction Worksheet for Self-Employed in Chapter 5 of IRS Pub 560. The 415(c)(1)(A) limit appears on line 8 of that worksheet.
Be aware that TurboTax and that worksheet do not directly handle the case where you also made elective deferrals or Roth contributions to a similar plan and another employers. Of course that subject to the 402(g) limit, not the 415(c) limit, but I though it was worth mentioning.
