I would think Schedule C line 13 would equal Form 4562 line 22, but it isn't close. Clicking on Schedule C line 13 doesn't help

You can Data Source Schedule C line 13 to see how that amount is calculated. You can also check Schedule C Part III to see if any depreciation was entered in that section. 

1. Click on Forms mode (top right of TurboTax)

2. Click on Schedule C under Forms in My Return. 

3. Go to Line 13 and right click right on the amount listed on line 13. A list pops up once you right click and you can        click Data Source

4. A box will pop up that shows how the amount on Schedule C line 13 is calculated. Click on the screenshot below for a      visual reference.