Skip to main content

NMEA 0183 Device Connections

This diagram illustrates two-way connections for both sending and receiving data. You can also use this diagram for one-way communication.

To receive information from a NMEA® 0183 device, refer to items 4 and 5 when connecting the Garmin® device.

To transmit information to a NMEA 0183 device, refer to items 6 and 7 when connecting the Garmin device.

For either NMEA 2000® or NMEA 0183 systems, refer to item 8 when making the basic power connections (Assigning Data to the Device), (Connecting the Device to Power).


Wiring diagram with callouts

Item

Description

1

12 Vdc power source

2

Power/NMEA 0183 cable

3

Optional switch (not included)1

4

Accessory On switch (not included)2

Wire

Garmin Wire Color

Garmin Wire Function

1

Red

Power

2

Yellow

Accessory On (NMEA 0183 systems)

3

Black

Power ground

4

Purple

RxA (+)

5

Gray

RxB (-)

6

Blue

TxA (+)

7

Brown

TxB (-)

8

Green

Silent mode (optional)3

1 Connecting the green wire to the power ground with a switch (not included) provides a toggle to temporarily revert to silent mode (receives only, does not transmit).
2 In NMEA 0183 systems, use the switch to power off the device when the boat engine is off, to avoid draining the battery.
3 Connecting the green wire to the power ground with a switch (not included) provides a toggle to temporarily revert to silent mode (receives only, does not transmit).
GUID-61A42529-ECEC-4B79-9F77-A5D87D90A579 v8
December 2025
© 2018 Garmin Ltd.