http://www.tomshardware.co.uk/forum/285978-32-device
Official response from WD Support Services:
"We were informed by Engineering that the message does not necessarily indicate a bad PCB and unfortunately, it is just an indication that the drive is malfunctioning (similar to a check engine light on a car). Unfortunately, here at support we have not seen a case where replacing the PCB would allow the data to be accessed (for cases where the PCB board was determined to be defective with certainty). Also, chances of finding the exact same revision PCB here at support would be nearly impossible as many different PCB revisions are used with the same exact models. Also Replacing the PCB could significantly reduce the chances of data recovery by a professional data recovery company. Data recovery requires advanced knowledge and equipment to recover and reconstruct, file and data structures and that is why we recommend using a professional data recovery company as they have a high success rate in recovering data"