If you efiled your return, you can't change the direct deposit info using TurboTax.
Once the IRS releases the refund (watch here https://www.irs.gov/Refunds ) it is then up to your bank to receive and post the deposit. This can take up to 3 business days to happen as they check to see if it is a legitimate deposit. If the routing & account numbers are correct AND if your name is on the account then the deposit should be acknowledged. If any of these things are incorrect the bank can refuse the deposit and the IRS will convert the refund to a paper check mailed to the address on the return. This process of conversion can take 2 weeks or more to happen.