Periodic Maintenance; Equipment Calibration; Vor Checks - Garmin GNS 480 Installation Manaul

Periodic Maintenance

6 Periodic Maintenance

6.1 Equipment Calibration

No scheduled servicing tasks are required on the GNS 480. The GNS 480 design requires no internal
manual adjustments.

6.2 VOR Checks

Even though the GNS 480 is designed to utilize the most state-of-the-art DSP technology and maintain a
very high accuracy and repeatability record, it still must undergo the VOR accuracy check required for
IFR flight. Refer to CFR 14 paragraph 91.171. Every 30 days verify the limits of the permissible indicated
bearing error.
The last VOR check information may be entered into the GNS 480 via the NAV VOR Mode then on the
Test Log Menu page.
6.3 Cleaning
The front bezel, keypad, and display can be cleaned with a soft cotton cloth dampened with clean water.
DO NOT use any chemical cleaning agents. Care should be taken to avoid scratching the surface of the
display.
6.4 Battery Replacement
The GNS 480 includes an internal battery that will last about 10 years. The battery is used for internal
RAM memory and GPS system information. Regular planned replacement is not necessary. The GNS 480
will display a "low battery" message when replacement is required. Once the low battery message is
displayed, the battery should be replaced within 1 to 2 months.
If the battery is not replaced and becomes totally discharged, the GNS 480 will remain fully operational,
but the GPS signal acquisition time will be increased. This acquisition time can be reduced by entering a
new seed position each time the unit is powered on. There is no loss of function or accuracy of the GNS
480 with a dead battery.
The battery is not user replaceable. To replace the battery, contact the Garmin AT repair station or factory
authorized repair station.
6.5 Display Backlight
The display backlight is rated by the manufacturer as having a usable life of 20,000 hours. This life may
be more or less than the rated time depending on the operating conditions of the GNS 480. Over time, the
backlight will dim and the display will not perform as well in direct sunlight conditions. The user must
determine by observation when the display brightness is not suitable for its intended use. Contact Garmin
AT repair station or factory authorized repair station when the backlight requires service.
GNS 480 (CNX80) Installation Manual 560-0982-01 Rev L 6-1