Hi, thank you for contacting JustAnswer.com. My name is Russell. I will do my best to provide the right answer to your question.
5 years might cause a battery inside a Forerunner watch to leak and corrode. That definitely fits what you have mentioned.
If the watch is 'dead', it may take some expense to repair it.
Sending it to Garmin Repair may be the only thing to do for it. I can quote the repair charge for your model:
And you can engage Garmin Repair through the link at the bottom of this page:
Let me know what you think, and what you would prefer, please. Thanks.
I agree. That sort of problem would be severe, even for a Factory Service Center to repair.
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