If you have not yet filed your return:
Under the File tab: You can change or edit the banking information that is shown, by making sure that the box stating 'I want my refund deposited into this account' is unchecked. Make sure that this box is not checked.
Scroll down to the bottom of the page and select Continue.
You will be taken to a new screen titled, "Let's get your bank account info". This will allow you to enter the new or updated banking information that is to be used for your 2016 direct deposit.
If you have already filed, you won't be able to change the banking info. The IRS will issue a paper check if the banking info does not match the taxpayer data.