Small one got a cap which looks like is bridging both pin outs.
I initially though the big one might be diagnostic/NMEA one but what is strange both small and big are just wired to 2 thin cables seen on the 2nd photo. I don't think they are there to pass any current, more for some kind of signalling - maybe RPM/trim but why those 2 socket in the bilge ?
That’s not a Suziki diagnostic plug. The diag plug is square and 4 pin with three wires out of it. I seem to recall there are options for additional gauges on my DF so it’s probably something to do with that or possibly flybridge additional displays.