hard to know...two things to check
1) Go back to the charity donations section nd make sure every charity donation is correct. Occasionally, a person puts a comma instead of a decimal for the cents, and that comma results in a large number.
2) If you made a large donation last year, that exceeded the AGI limit for donations last year, you might have had some $$ carryover to this year's forms.
Other than that, you'd need to make a printout of your tax return (actually, just a PDF file) from the Print Center, with all forms and worksheets, to find the various charity worksheets that recorded exactly what you entered...but #1 above should show where the problem occurred in most cases.
Where exactly does TurboTax "display" $14,975? If it's on a TurboTax screen, what screen? Where is it in TurboTax? What is the exact heading or title on the screen? What is the description of the $14,975 amount on the screen? Can you post a screen shot? If the amount is on a tax form, what form and line number?
Did you use Its Deductible?
Do you have any non-cash donations?