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Considering its an Approach S2 that you have. The battery in that unit is past its expected life.
You need to replace the battery in the watch, this will also restore its performance and life on the course as well. The cheapest replacement service ive seen is listed here, at about half the cost garmin charges. http://amzn.to/1RRPtyz
Or, if you have a soldering iron you can purchase just the battery for 23$ and save some $$ http://amzn.to/1U9SL6J
As far as the Garmin approach and whether or not to repair it, or replace it. If the device has been working well, and its only the battery charging issue thats occured. I would replace the battery.
However, if youve noticed that some of the buttons are coming loose, or not working. Or the device has a lot of errors or sudden shutdowns, I wouldnt replace the battery as that would sound like the logic board is beginning to fail. If the only issue is the device charging, then replacing the battery should give you another 2-3 years of life barring any unforeseen accidents or damage to the unit.
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