Answer:
Under Reg Z typically it is the consumer who will detect and report the error. This places into motion the investigation which would have the lender bank and the bank owning the ATM talking to one another so that each can properly balance their books. If either the lending bank or ATM owning bank knew of the error they could start the process of correcting the error, but I know of nothing in Reg Z requiring this.
First published on BankersOnline.com 5/28/07