Garmin GNC 420AW, Installation Manual

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400W Series Installation Manual Page 8-1
190-00356-02 Rev. G
8. PERIODIC MAINTENANCE
8.1 Equipment Calibration
No scheduled servicing tasks are required on the 400W Series unit.
8.2 VOR Checks
Refer to CFR 14 paragraph 91.171. Every 30 days verify the limits of the permissible indicated bearing
error.
8.3 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.
8.4 Battery Replacement
WARNING
This product contains a Lithium battery that must be recycled or disposed of properly.
Battery replacement and removal must be performed by professional services.
The 400W Series unit includes an internal battery that will last 5 to 8 years. The battery is used for
internal time clock and GPS system information. Regular planned replacement is not necessary. The
400W Series unit will display a “Low Battery” and “Unit Needs Service” 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 400W Series unit will remain fully
operational, but the GPS signal acquisition time will be increased. There is no loss of function or accuracy
of the 400W Series unit with a dead battery.
The battery is not user replaceable. To replace the battery, contact the Garmin repair station or factory
authorized repair station.