26 Technical Reference for Garmin NMEA 2000 ProductsNMEA 2000-Certified Sensor Configuration InformationGRA 10 (Garmin Rudder Angle Adapter)Note: This section provides specific configuration information for the GRA 10 adapter using your compatible Garmin display device. Toaccess the NMEA 2000 configuration menu on your display device, consult the documentation provided with your display device.Calibrating the Rudder AngleTo use the GRA 10 adapter, you must calibrate the angle of the rudder that the adapter is associated with.1. Turn the boat ignition key to the On position (not Start).2. From the NMEA 2000 Devices list, select the GRA 10 device.3. Select an option:• For most Garmin chartplotters, select Review > Rudder Angle Calibration.• For other Garmin marine devices, select Config > Rudder Angle Calibration.4. Follow the on-screen instructions to calibrate the starboard and port rudder angles.5. Select OK when the calibration is complete.Troubleshooting the Gauge TypeWhen connected to a gauge, the GRA 10 adapter gauge type is set to auto Detect by default, and the adapter automatically detects the type ofgauge it is connected to. If the rudder-angle reading on a connected Garmin chartplotter or marine instrument changes with the engine RPM, theadapter may be detecting the wrong type of gauge.To test the gauge-type setting:1. When the boat is not moving, put the engine in neutral.2. Use the throttle to increase the engine RPM. If the rudder-angle reading changes with the engine RPM, change the gauge type.To change the gauge type:1. From the NMEA 2000 Devices list, select the GRA 10 device.2. Select an option:• For most Garmin chartplotters, select Review > Gauge Type.• For other Garmin marine devices, select Config > Gauge Type.3. Select an option:• To automatically detect the gauge type, select Auto Detect.• To indicate a one-coil gauge, select 1 Coil.• To indicate a two-coil gauge, select 2 Coil.4. Perform the gauge-type setting test.Configuring the GRA 10 Adapter if the Rudder Angle Calibration and Gauge Type Selections Are NotDisplayedDepending on the version of software loaded on your Garmin marine instrument, the specific configuration options may not be displayed on theconfiguration screens.To calibrate the rudder angle if the menu option is not displayed:To use the GRA 10 adapter, you must calibrate the angle of the rudder that the adapter is associated with.1. Turn the boat ignition key to the On position (not Start).2. From the NMEA 2000 Devices list, select the GRA 10 device.3. Select an option:• For most Garmin chartplotters, select Review > Generic Config.• For other Garmin marine devices, select Config >Generic Configuration.4. Move the rudder fully to starboard and observe the angle of the rudder position, in degrees.5. Enter the following command: “RUDDERPOS=”