Hi and welcome to JustAnswer,Thank you for the question and your patience. Should you still need assistance for information purposes only...Initially, do the boards have the same part numbers? ...appear to be identical?
Have you verified the pinouts of the connectors?
Hi again Barry and appreciate the post back.
Even the Service Manuals does not list an error code FV7 hence the above / initial post.
It would seem that even if the power supply may look identical, the pinout particularly of the 15-pin connector is NOT the same.
Offhand, it would appear that a modification is required to match the DMR-EH58's PSU to the DMR-EH67 main board.