Problem

Possible Cause

Action

Display shows “Incorrect Calibration Checksum” at start-up

Corrupted system calibration parameters

Contact factory

Table 4-1 Troubleshooting

4.2Updating the Frequency Database

The GNC 255 uses a standard USB memory device to load the frequency database into the GNC 255. The memory device is not provided by Garmin. The Frequency database is stored internally and the USB memory device is only used to transfer the database into the unit.

The Garmin databases can be updated by following the instructions on https://fly.garmin.com/fly-garmin.

The following equipment is required to perform the update:

Windows-compatible PC computer (Windows 2000, XP, Vista, or Windows

7 recommended)

USB 2.0 compatible USB flash drive

External USB cable

Updated database obtained from the Garmin web site

NOTE: The data contained in the frequency database comes from government agencies. Garmin accurately processes and cross-validates the data, but cannot guarantee the accuracy and completeness of the data.

4.2.1Downloading the Frequency Database

The Frequency database is updated on a 28-day cycle. Frequency database updates are provided by Garmin and may be downloaded from the Garmin web site https://fly.garmin.com/fly-garmin.

4.2.2Updating the GNC 255 Frequency Database

See Section 3.5.5 for details on updating the database.

190-01182-01 Rev. A

Garmin GNC 255A/255B Pilot’s Guide

4-3

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Image 55
Garmin 255A manual Updating the Frequency Database