Not sure if that's even possible beyond the immediate previous firmware which is stored as a backup. It's further complicated for me by the fact that my watch needs the APAC version of any old firmware.

Yes, with APAC devices it is not possible, but there are countless of Instinct Solar non-APAC owners who, in the past, downloaded the beta side-load packages which always contain also the previous release version of the firmware. So it would interesting to hear from them and see whether the firmware is to be blamed or whether it is rather a hardware problem. Personally, I have the non-solar old Instinct, and it still works fine, so cannot help with the testing.

Hi Chris. I am in Portugal and having the same problem for the last weeks. I´ve tried to contact Garmin assistance by mail but after several tries seems that it is not being sent (som sort of issue I do not understand with Garmin assistance). I have done the hard reset and updated the software in Garmin Express. No success. Keeps shutting of. I stopped using the watch to activities and now even for regular use. Can you help with any recommendation to solve this out?

Instinct® Solar, SERIAL NUMBER: 6L3136597

+Garmin - Chris

From the web site - Instinct® Solar – Standard Edition | Garmin | Portugal | Centro de Assistência

I got the same issue...the watch automatically shut down when I start an activity, may you share the way how to fix it?

Turn off vibration for activities and alarms, it seems to help. Apart from that there's no solution as it is a hardware problem. 

Hi Chris, I have messaged garmin about this issue as mine has been doing it for the last few weeks. Someone mentioned you’ve fixed it for them. I’m worried that mine is over 2 years old and they won’t fix it, and I can’t afford a replacement. Can you help? I tried the hard reset but no luck. 

My watch keeps shutting off randomly too. Started a couple weeks ago while hiking around our property and tracking my activity with GPS. I initially just thought it was sucking the battery down, but was only out ~45 min and remembered I had just charged it fully. Since then it cuts out almost every other day. Went off today 3 separate times. Immediately after I plug the watch in to charge, it shows 50-60% battery. This is extremely frustrating to say the least

Typical signs of the battery reaching end of life. Contact Garmin support in your country and see what they will do. Mine was less than 2 years and Garmin Australia replaced it. In other countries, with less strict consumer protection laws, you may not be so lucky.

I had firstly noted that mine was shutting down randomly and worked out that it was when alarms were going off: the battery couldn't support the high current draw even when it was 50% charged. It would then crash shortly after starting GPS activities. The only way to restart the watch was to plug it into a charger, and like in your case it would immediately show 50 to 60% charged. I don't believe it is a firmware issue. My replacement is over a year old now and is working fine, despite several software updates.

I had tried various things like factory resets, loading older versions of firmware, fully discharging and charging the battery etc. Sometimes I thought that the problem was solved, but it never was. Had the same problem with a mobile phone and tablets and replacement of the failing battery is the only option. In the case of the watches that means a replacement watch

Hi All, this also happened with me after several email with Garmin support. I reported two watches including date of purchase with same shutting off issue. initially support already identified the issue was hardware and said that they will replace it under warranty, then I was forwarded to regional support and said I need to bring the watches to a service center for troubleshooting, charges may apply if device is not within warranty. I asked the service center how much is the replacement and it's the same price of a new one. With this kind experience Garmin is basically saying our watch is only good for one year.