What smartcraft unit do you have , CS1000 , SC5000 or vesselvieuw ?
I first had my SC1000 connected to my lowrance , then added the SC5000 to the SC1000 and now i have a vesselvieuw hooked up to the SC1000 and all work instandly on the lowrance cartplotter via the nmea connection (blue-white/wite wire)
If i remember right the blue-white wire connects to the ground and the white connects to the nmea+ wire .
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