Except with respect to a self-employed health insurance deduction, you are not self-employed. The deduction for the 401(k) contributions made by your S corp to your 401(k) account is reportable on your S corp's tax return, not your personal tax return. The only thing regarding your 401(k) that is entered into TurboTax for your personal tax return is to enter into box 12 of TurboTax's W-2 form any entries in box 12 of the W-2 issued to you by the S corp.
