Garmin GNX 20 Manuals

GNX™ 20/21 Installation Instructions To obtain the best possible performance, install this marine instrument according to these instructions. If you experience difficulty during the installation, contact Garmin ® Product Support, or seek the advice of a professional installer. This instrument communicates with NMEA 2000 ® sensors and devices, and shows information such as speed, heading, and water depth when connected to the appropriate sensors. The instrument can also communicate with a NMEA ® 0183 device using an optional data cable. Important Safety Information WARNING See the Important Safety and Product Information guide in the product box for product warnings and other important information. CAUTION Always wear safety goggles, ear protection, and a dust mask when drilling, cutting, or sanding. NOTICE When drilling or cutting, always check what is on the opposite side of the surface. Registering Your Device Help us better support you by completing our online registration today. • Keep the original sales receipt, or a photocopy, in a safe place. Mounting Considerations NOTICE This device should be mounted in a location that is not exposed to extreme temperatures or conditions. The temperature range for this device is listed in the product specifications. Extended exposure to temperatures exceeding the specified temperature range, in storage or operating conditions, may cause device failure. Extreme-temperature-induced damage and related consequences are not covered by the warranty. The mounting surface must be flat to avoid damaging the device when it is mounted. Using the included hardware and template, you can flush mount the device in the dashboard. If you want to mount the device using an alternative method where it appears flat with the front of the dashboard, you must purchase a flat-mount kit (professional installation recommended) from your Garmin dealer. When selecting a mounting location, observe these considerations. • The mounting location should be at or below eye level to provide optimal viewing as you operate your vessel. • The mounting location should be at less than a 45° viewing angle for the GNX 20 Marine Instrument with Standard LCD and less than a 50° viewing angle for the GNX 21 Marine Instrument with Inverted LCD. Screen color inversion occurs when the viewing angle is greater than 30° in the 9 o'clock direction on the GNX 20 and when the viewing angle is greater than 60° in the 1 o'clock direction on the GNX 21. • The mounting location should allow easy access to the keys on the device. • The mounting surface must be strong enough to support the weight of the device and protect it from excessive vibration or shock. • To avoid interference with a magnetic compass, the device should not be installed closer to a compass than the compass-safe distance value listed in the product specifications. • The area behind the mounting surface must allow room for the routing and connection of the cables. Mounting the Device NOTICE If you are mounting the device in fiberglass, when drilling the four pilot holes, it is recommended to use a countersink bit to drill a clearance counterbore through only the top gel-coat layer. This will help to avoid any cracking in the gel-coat layer when the screws are tightened. Stainless-steel screws may bind when screwed into fiberglass and overtightened. Garmin recommends applying an anti-seize lubricant to the screws before installing them. The included template and hardware can be used to flush mount the device in your dashboard. To mount the device so the screen is flat with the dashboard, you must purchase a flat- mount kit from your Garmin dealer. 1 Trim the flush-mount template and ensure it will fit in the location where you plan to mount the marine instrument. The flush-mount template is included in the product box. 2 Remove the liner from the adhesive on the back of the template and apply it to the location where you plan to mount the marine instrument. 3 If you plan to cut the hole with a jigsaw instead of a 90 mm (3.5 in.) hole saw, use a 10 mm (3/8 in.) drill bit to drill a pilot hole to begin cutting the mounting surface. 4 Using the jigsaw or the 90 mm (3.5 in.) hole saw, cut the mounting surface along the inside of the dashed line indicated on the flush-mount template. 5 If necessary, use a file and sandpaper to refine the size of the hole. 6 Place the marine instrument into the cutout to confirm that the mounting holes on the template are in the correct locations. 7 If the mounting holes are not correct, mark the correct locations of the mounting holes. 8 Remove the marine instrument from the cutout. 9 Drill the 2.8 mm (7/64 in.) pilot holes. If you are mounting the marine instrument in fiberglass, use a countersink bit as advised in the notice. 10Remove the remainder of the template. 11Place the included gasket on the back of the device and apply marine sealant around the gasket to prevent leakage behind the dashboard. 12If you will not have access to the back of the device after you mount it, connect all necessary cables to the device before placing it into the cutout. NOTE: To prevent corrosion of the metal contacts, cover unused connectors with the attached weather caps. 13Place the marine instrument into the cutout.

GNX™ 20/21 Installation Instructions To obtain the best possible performance, install this marine instrument according to these instructions. If you experience difficulty during the installation, contact Garmin ® Support, or seek the advice of a professional installer. This instrument communicates with NMEA 2000 ® sensors and devices, and shows information such as speed, heading, and water depth when connected to the appropriate sensors. The instrument can also communicate with a NMEA ® 0183 device using an optional data cable. Important Safety Information WARNING See the Important Safety and Product Information guide in the product box for product warnings and other important information. CAUTION To avoid possible personal injury, always wear safety goggles, ear protection, and a dust mask when drilling, cutting, or sanding. NOTICE When drilling or cutting, always check what is on the opposite side of the surface to avoid damaging the vessel. Mounting Considerations NOTICE This device should be mounted in a location that is not exposed to extreme temperatures or conditions. The temperature range for this device is listed in the product specifications. Extended exposure to temperatures exceeding the specified temperature range, in storage or operating conditions, may cause device failure. Extreme-temperature-induced damage and related consequences are not covered by the warranty. The mounting surface must be flat to avoid damaging the device when it is mounted. When selecting a mounting location, observe these considerations. • The mounting location should be at or below eye level to provide optimal viewing as you operate your vessel. • The mounting location should be at less than a 45° viewing angle for the GNX 20 Marine Instrument with Standard LCD and less than a 50° viewing angle for the GNX 21 Marine Instrument with Inverted LCD. Screen color inversion occurs when the viewing angle is greater than 30° in the 9 o'clock direction on the GNX 20 and when the viewing angle is greater than 60° in the 1 o'clock direction on the GNX 21. • The mounting surface must be strong enough to support the weight of the device and protect it from excessive vibration or shock. • To avoid interference with a magnetic compass, the device should not be installed closer to a compass than the compass-safe distance value listed in the product specifications. • The area behind the mounting surface must allow room for the routing and connection of the cables. Mounting the Device NOTICE If you are mounting the device in fiberglass, when drilling the pilot holes, use a countersink bit to drill a clearance counterbore through only the top gel-coat layer. This will help to avoid cracking in the gel-coat layer when the screws are tightened. The included template and hardware can be used to flush mount the device in your dashboard. 1 Trim the flush-mount template and ensure it fits in the location where you plan to mount the marine instrument. The flush-mount template is included in the product box. 2 Remove the liner from the adhesive on the back of the template and adhere it to the location where you plan to mount the marine instrument. 3 If you plan to cut the hole using a rotary tool instead of a 90 mm (3.5 in.) hole saw, use a 10 mm (3/8 in.) drill bit to drill a pilot hole to begin cutting the mounting surface. 4 Using the 90 mm (3.5 in.) hole saw or rotary tool, cut the mounting surface along the inside of the dashed line indicated on the flush-mount template. 5 If necessary, use a file and sandpaper to refine the size of the hole. 6 Place the marine instrument into the cutout to confirm that the mounting holes on the template are in the correct locations. 7 If the mounting holes are not correct, mark the correct locations of the mounting holes. 8 Remove the marine instrument from the cutout. 9 Drill the 2.8 mm (7/64 in.) pilot holes. If you are mounting the marine instrument in fiberglass, use a countersink bit as advised in the notice. 10Remove the remainder of the template. 11Place the included gasket on the back of the device and apply marine sealant around the gasket to prevent leakage behind the dashboard. 12If you will not have access to the back of the device after you mount it, connect all necessary cables to the device before placing it into the cutout. NOTE: To prevent corrosion of the metal contacts, cover unused connectors with the attached weather caps. 13Place the marine instrument into the cutout. 14Securely fasten the marine instrument to the mounting surface using the supplied screws. If you are mounting the marine instrument in fiberglass, use a anti-galling lubricant as advised in the notice. 15Snap the bezel into place. GUID-E313CF8B-397D-48AF-8839-977C29E188D5 v4 August 2020

GNX™ 20/21 Installation Instructions To obtain the best possible performance, install this marine instrument according to these instructions. If you experience difficulty during the installation, contact Garmin ® Product Support, or seek the advice of a professional installer. This instrument communicates with NMEA 2000 ® sensors and devices, and shows information such as speed, heading, and water depth when connected to the appropriate sensors. The instrument can also communicate with a NMEA ® 0183 device using an optional data cable. Important Safety Information WARNING See the Important Safety and Product Information guide in the product box for product warnings and other important information. CAUTION Always wear safety goggles, ear protection, and a dust mask when drilling, cutting, or sanding. NOTICE When drilling or cutting, always check what is on the opposite side of the surface. Registering Your Device Help us better support you by completing our online registration today. • Keep the original sales receipt, or a photocopy, in a safe place. Mounting Considerations NOTICE This device should be mounted in a location that is not exposed to extreme temperatures or conditions. The temperature range for this device is listed in the product specifications. Extended exposure to temperatures exceeding the specified temperature range, in storage or operating conditions, may cause device failure. Extreme-temperature-induced damage and related consequences are not covered by the warranty. The mounting surface must be flat to avoid damaging the device when it is mounted. Using the included hardware and template, you can flush mount the device in the dashboard. If you want to mount the device using an alternative method where it appears flat with the front of the dashboard, you must purchase a flat-mount kit (professional installation recommended) from your Garmin dealer. When selecting a mounting location, observe these considerations. • The mounting location should be at or below eye level to provide optimal viewing as you operate your vessel. • The mounting location should be at less than a 45° viewing angle for the GNX 20 Marine Instrument with Standard LCD and less than a 50° viewing angle for the GNX 21 Marine Instrument with Inverted LCD. Screen color inversion occurs when the viewing angle is greater than 30° in the 9 o'clock direction on the GNX 20 and when the viewing angle is greater than 60° in the 1 o'clock direction on the GNX 21. • The mounting location should allow easy access to the keys on the device. • The mounting surface must be strong enough to support the weight of the device and protect it from excessive vibration or shock. • To avoid interference with a magnetic compass, the device should not be installed closer to a compass than the compass-safe distance value listed in the product specifications. • The area behind the mounting surface must allow room for the routing and connection of the cables. Mounting the Device NOTICE If you are mounting the device in fiberglass, when drilling the four pilot holes, it is recommended to use a countersink bit to drill a clearance counterbore through only the top gel-coat layer. This will help to avoid any cracking in the gel-coat layer when the screws are tightened. Stainless-steel screws may bind when screwed into fiberglass and overtightened. Garmin recommends applying an anti-seize lubricant to the screws before installing them. The included template and hardware can be used to flush mount the device in your dashboard. To mount the device so the screen is flat with the dashboard, you must purchase a flat- mount kit from your Garmin dealer. 1 Trim the flush-mount template and ensure it will fit in the location where you plan to mount the marine instrument. The flush-mount template is included in the product box. 2 Remove the liner from the adhesive on the back of the template and apply it to the location where you plan to mount the marine instrument. 3 If you plan to cut the hole with a jigsaw instead of a 90 mm (3.5 in.) hole saw, use a 10 mm (3/8 in.) drill bit to drill a pilot hole to begin cutting the mounting surface. 4 Using the jigsaw or the 90 mm (3.5 in.) hole saw, cut the mounting surface along the inside of the dashed line indicated on the flush-mount template. 5 If necessary, use a file and sandpaper to refine the size of the hole. 6 Place the marine instrument into the cutout to confirm that the mounting holes on the template are in the correct locations. 7 If the mounting holes are not correct, mark the correct locations of the mounting holes. 8 Remove the marine instrument from the cutout. 9 Drill the 2.8 mm (7/64 in.) pilot holes. If you are mounting the marine instrument in fiberglass, use a countersink bit as advised in the notice. 10Remove the remainder of the template. 11Place the included gasket on the back of the device and apply marine sealant around the gasket to prevent leakage behind the dashboard. 12If you will not have access to the back of the device after you mount it, connect all necessary cables to the device before placing it into the cutout. NOTE: To prevent corrosion of the metal contacts, cover unused connectors with the attached weather caps. 13Place the marine instrument into the cutout.

GNX™ 20/21 Owner’s Manual March 2016 190-01659-00_0C

GNX ™ 20/21 Owner’s Manual February 2014 190-01659-00_0B Printed in Taiwan