2004 Mercury 200 outboard Smartcraft not working properly.

[TOMZILLA]

I just bought a 04 Mako 215 WA with a 200 Merc OB. The problem I'm having is the Smartcraft head unit is only showing total fuel burned and the temperature which is way wrong @ 32 on a 78 degree day. For hours it only shows bars -------.

I've checked the wiring at the motor, unplugged and plugged and the same at the gauge. The only other thing I can find which may or maynot be wrong. Is at the diagnostic plug #84-859316 A1 there is a grey wire unplugged and appears nowhere to plug it into. So I assume its for diagnostics hookup...

 

[tommarvin]

It may be on you tube, look it up on google, it looks like a Mercury oem product.
You might be able to find the manual for it from Mercury
Pull all the wires in the connectors hard, a wire could be broken inside and just hanging in there.
We have a 1984 Mako 224 CC, twin 115hp four stroke EFI, Do you think Mako boats are the greatest boats on earth too?

 

[TOMZILLA]

I checked the wiring and appeared all to be good. I could check again. I'm just wondering if this is the symptoms of a bad head unit.

As far as Mako boats this is my first one. I've had Trophy, Wellcraft, Cobia and Silverhawk. Mako seems like a good boat but after owner my 24 CC Silverhawk its hard for others to measure up. Only sold it being it was a little big to be hauling 400 miles a fishing trip.

 

[schematic]

are you equipped with analog gauges as well? If so, are they working properly?