Hi, thank you for contacting JustAnswer.com. My name is Russell. I will do my best to provide the right answer to your question.
I would advise you to first consider how old the Garmin device is. If it has been running off the same rechargeable battery inside it for several years or longer, it may have a failing battery that no longer holds charge or delivers insufficient voltage, and causes the device to shut down again immediately.
Or, it may be that the system software on the Garmin device has become corrupted and is in need of updating perhaps.
For the first, you can determine whether that is the problem, by powering it up while it is still on the charger, and if it stays On that way for any considerable period, then the battery is insufficient to power it and needs replacing.
As for the second, you can try to update it by connecting it to a computer with Garmin Express loaded upon it. Garmin Express may be obtained (for either Windows PC or Apple computer) as follows:
Simply download, install, and use Garmin Express.
and (if you have a Windows PC) click on the big blue Download button at center bottom of the page. (If you have an Apple, click on the nearby Download for Mac link.) And download Garmin Express' installer to your computer, save it, then double-click upon it to install Garmin Express.
Then start the program, Garmin Express. Then connect your Garmin device. Then use Garmin Express to update your device.
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OK, I see.
Is it running off the boat's power supply? if so, double-check on the power supplied to it. In such a situation, it is unlikely to be a battery problem.
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