Furuno GP3-400-N2K-06 6M NMEA 2000 Cable for GP340

The Furuno GP3-400-N2K-06 is the factory 6-meter cable that connects a GP340 GPS navigation antenna to your boat's NMEA 2000 network. It's a simple part, but it's the right part. Furuno builds it with the correct connector and pinout for the GP340, so you're not guessing at wiring or hunting for adapters when it's time to rig up. Buy the cable that's made for the antenna and the install goes a lot smoother.

The GP340 antenna can output its position data in two formats, NMEA 2000 or NMEA 0183. This is the NMEA 2000 version. One end terminates in a standard N2K Micro connector that drops straight onto a backbone spur or tee. If your helm electronics already talk on an NMEA 2000 backbone, this is the cleaner, more modern way to bring GPS into the network. The antenna sends its fix down the same cable that powers it, so there's no separate power run to deal with.

We've rigged the GP340 on everything from 25-foot center consoles to 40-foot sportfishers, and 6 meters covers most antenna-to-console runs on boats in that range. On a typical center console you'll mount the antenna up on a hardtop or arch and drop the cable down through the tube to the N2K backbone at the helm. On a sailboat, plan your route through the mast conduit and give yourself a little slack. The black jacket takes UV well, but it does stiffen up in cold weather, so a bit of cable lube makes pulling it through tight conduit a lot easier.

What if 6 meters isn't enough? It happens on bigger boats and on runs where the antenna sits a long way from the helm. Don't try to stretch a single drop past what it's rated for. The right move is to extend your NMEA 2000 backbone toward the antenna with a backbone segment and a tee, then land this cable on that closer tee. That keeps every spur inside spec and keeps your network healthy. Voltage drop on an over-long drop is a real thing, and it tends to show up as intermittent GPS on longer powerboats right when you don't want it to.

A quick word on the network itself, since it trips people up. An NMEA 2000 backbone needs a terminator at each end, one male and one female. The GP340 on this cable is a spur off that backbone, not part of the backbone itself. If you're adding the GP340 to an existing, properly terminated network, you just tee in and go. If you're building the network from scratch, get your two terminators sorted first. The antenna draws very little current, so you won't need an extra fuse as long as it's on a protected, powered spur.

One habit that pays off: put a dab of dielectric grease on the connector before you seat it. NMEA 2000 plugs live in a wet, salty world, and a connector that's left dry can corrode over a season and give you an intermittent signal that's maddening to chase down. Grease it, seat it fully until it clicks, and you'll forget it's there. That's exactly what you want from a GPS feed, quiet and reliable in the background.

This is the cable to buy if you own a GP340 and you're running an NMEA 2000 helm. It's the exact part Furuno ships for the job, in the length that fits most boats, with the connector that drops onto your backbone without fuss. If you're on an older NMEA 0183 setup instead, that's a different cable, so check your antenna's output format before you order. Not sure which one you've got? Give us a call and we'll sort it out with you.