How to Update the 2020 IGRF Magnetic Field Model (Mag/Var) for your Avionics

The IGRF (International Geomagnetic Reference Field) is a standard mathematical description of the Earth's main magnetic field. It is updated every 5 years; therefore, Garmin® avionics require an update to reflect this change.

When updating Navigation Data to cycle 2012 or later, your avionics will prompt you to update the IGRF model GRS1 MV DB (Magnetic Variation Database). You can accept it and proceed with the update.

However, certain systems are equipped with software versions that require specific attention. Therefore, you may notice that the IGRF model update might fail. If it does fail, then take a look at the following Service Advisories and select the link that applies to your specific avionics.

1. For all G1000®, G900X®, G950®, G1000H®, G1000® NXi, Cirrus Perspective, Embraer Prodigy flight decks with a Garmin AHRS and GDU software versions 6.00 and greater. Also, for All Garmin G2000®, G3000®, G5000®, G5000H™, and Embraer Prodigy flight decks with a Garmin AHRS, please see Service Advisory 1612, Rev F.
2. Within the Service Advisory, on Step 2, you will need to open that link on your browser. It will take you here:
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3. Follow the steps shown in the above picture while using a Windows PC. When using Google Chrome as your main browser, right-click on the download link and click "Copy Link Address."
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4. Open a new tab on your browser, and paste the text. This will start downloading the .exe file.
   • For all G500, G500H, G600, G500 TXi™, G500H TXi, G600 TXi, G700 TXi, and GI 275 displays, see Service Advisory 20112 Rev A.

Notes:

• If you are not able to update your IGRF file with the above procedures, contact your local Garmin Dealer for further assistance.
• For G3X Touch™ avionics, these will receive the 2020 IGRF file with a G3X Touch software update to software version 9.00.

Watch this video for more information about the International Geomagnetic Reference Field.