Marine engine scan tool
 

I have a Tech Mate scan tool that can pull codes and read data from most computer-controlled (MEFI and ECM555) marine inboards and stern drives. If you are the DIY type and find yourself stumped by an issue that requires a scan tool, I can probably help you out. Unlike OBD scanners for a car, marine scan tools aren't cheap or common...

I'll vouch for Dave and his scan tool! :)

After he visited, I was wishing I had one, but they cost a few hundred dollars!