Paddle Speed Sensor with MercMonitor ECO

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Bought an 2003 Utopia with a replaced engine and a hack job of a wiring job. Looks like they installed the MercMonitor because the couldn't the gauges to work after they got the engine in. I got the fuel gauge working after changing wiring and a new sender but can't figure out the speed. The MercMonitor says its disconnected and I tried tracing wiring and it doesn't look to be plugged in.

I found documentation on the getting a separate harness (SmartCraft Fuel/Paddle/Oil Boat Harness) to integrate with the gauge but the wiring schematics look to have a 4 wire sensor with the sea temp sensor built in but mine only has 2 wires like stock sensor.


Found a couple unplugged connectors. The one with the multimeter probes is the largest and the second picture looks to be the old speedo harness. I have tried probing them while having someone spin the paddle but no luck there.

Any ideas what needs to be done here or at least the stock wiring diagram for these boats??

That first pic is definitely the speedo connector. The second looks to be the fuel gauge or tach. I'll see if I can go compare wires in a bit. My speedo didn't work, and I tried to troubleshoot the paddlewheel to no avail. Finally took out the speedo, got the needle unstuck and probed around with a multi meter and some voltages. When I hooked it back up, spinning the paddlewheel made the speedo move. It still gets stuck sometimes, but a gentle wrap on the glass usually "resets" it. All that being said, the sensor is probably OK.
I'll try and verity the other plug for you tonight.
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Beemah, your second pic is indeed the fuel gauge/oil light harness. I snapped pics of my 2003. Top pic is the fuel/oil on the left, speedo in the middle. Second pic is speedo, tach on the right. The speed sensor wires SHOULD be the Green and one of the Black (on the big, speedo plug). Maybe that will help you some. I know nothing of the MercMonitor system other than it exists, and I THINK my engine has the plug for it...
I you need any other pics or info from a stock setup, let me know! Good luck!
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