Mariner Outboards Electric Start Can Any One Help With Electrical Problem On 50hp Mariner Outboard?

Can any one help with electrical problem on 50hp Mariner outboard? - mariner outboards electric start

I have a 50 hp Mariner, which has an intermittent electrical fault.
Electric start and power tilt and trim. Although sometimes it is normally the starter just clicks like a starter motor disorders. At the same time, the links to complain to the slope and cut himself, but do not activate the device. The two failures occur simultaneously and are available only intermittently. All other facilities are good and we are working all the time, even if the starter is at fault. It is done something, but not enough to move to the starter. All batteries are fully charged.

I had the electrical system and controls all seemed well, although the error was obvious at the time. Maybe a ground could be on the engine, but everything seems okay.

No one had the same problem and can advise me where to start looking.