Loading the New Software on a Memory Card Using Garmin Express
You can copy the software update to a memory card using a computer with the Garmin Express™ app.
The internal card readers on GPSMAP® 8400 and 8600 series chartplotters support up to 32 GB memory cards, formatted to FAT32 with speed class 4 or higher1. Use of an 8 GB or larger memory card with speed class 10 is recommended. As of software version 34.00, the internal card readers on GPSMAP 9000 series chartplotters support up to 1 TB memory cards, formatted to exFAT with speed class 10 or higher.
Downloading the software update may take from a few minutes up to a few hours.
You should use a blank memory card for software updates. The update process erases the content on the card and reformats the card.
After loading the update onto the memory card, install the software on the chartplotter (Updating the Device Software Using a Memory Card).