Internal Backup Battery for Garmin GPSmap and StreetPilot

This battery is used in a number of the GPSmap and StreetPilot models;
GPSmap 440, 515, 521, 535, 540, 541, 545, 546, 695, 696, 740
Street Pilot 2820, 2720, 2730, 2710, 2610, 2620, 2650, 7200, 7500

Rechargable Internal backup battery

To test the battery, turn the unit on for a few minutes then turn the unit off and wait 10 minutes before measuring the voltage at the internal battery contacts, if the volgate is below 2 VDC then the battery is not holding and should be replaced.

The backup battery is required to maintain the GPS location values while the unit is turned off, with a bad battery each time the unit is turned on the satellite acquisition takes five to ten minutes and with a good backup battery the acquisition takes around 30 seconds if you have not moved from the last location.