Download and install the latest software update for Garmin GPSMAP 430 :http://www8.garmin.com/software/ChartplottersUpdatewithSDcard_20120213.exeInstallation Instructions:
Click on 'Download' and choose to save the file to your computer.
Choose a location where you can easily find the file, such as the 'My Documents' folder or 'C:\'.Once the download is complete, go to the location where you saved the file.
Double-click on the downloaded file. This will automatically extract the files to C:\Garmin and run a program to transfer the software update to an SD card.
Power on the device and make sure all other connected devices are powered on as well.
Insert the card into the card slot of your primary device. Select 'Update Software' in the window that automatically displays. If you do not have a primary device with a card slot, please see your dealer.
After the update completes, the chartplotter containing the SD card and all NMEA 2000 sensors will have the latest software. Note: If you have additional chartplotters connected to NMEA 2000, you will have to independently update each chartplotter. After the update completes, insert the update card into each NMEA 2000 chartplotter.
2.Restore your GPS to factory settings:
Note: This procedure deletes any information you have entered.
1.From the home screen,select Configure > system>System information>factory settings.
2.Select Yes to restore all factory settings,or select No to cancel.
If you have questions or need further assistance ,please let me know.
The unit reboots and prompts you to adjust unit settings .