fault code / lights Optimax EFI 250 two stroke

[Fishermark]

Twin Mercury Optimax EFI 250 2 stroke outboards on a 1992 Fountain. When I turn the key for the port engine, the alarm sounds and the lights flash for the oil and temp - alternating between the two.

Any thoughts as to why?

It is curious, it also flashes the port gauges / lights when I turn the key on for the starboard engine.

The video above should give you an idea of what I am talking about.

 

[schematic]

When things don't make sense..........CHECK FOR BAD or DISCONNECTED GROUND WIRES