Forerunner 255 battery drains fast after Software 16.17 updated

No problems at all. Shut down the watch en restart it after a minute. Mostly this solves it.

Have you got the pulse o2 settings turned to "on demand"? If not, it'll take pulse oxygen readings at regular intervals and drain your battery as described 

Thanks for the recommendation, i have changed to "on demand", let me monitor for few days.

I am on v16.17, pulse 02 is not turned to "on demand" and my watch doesn't drain in a day like what the OP describes.

My watch power consumption for my specific needs hasn't changed after 16.17, it was before and still is after, about a week. No change after this patch.

I'm not sure about others, but i have noticed the battery depleting fast after the update.. I only wear the watch when i am heading for run.. usually the watch is idle.

Yes I don't think that's normal, depleting almost the entire battery in a day sounds a bit extreme.

Are you using the GPS function ? Because I don't and my battery is fine, so perhaps if you do, then GPS is the problem ?

I don't think this is about settings. Sometimes some watches get into a wrong state after updates, and some software is stuck in a loop. The fix is usually some sort of restart.

My first charge with 16.17 ends before I expected. I didn't change any setting. I've just restarted the watch. Usually battery lasts for 10+ days with my usage, I will report again before 30th.

EDIT: 10 days done, stil have 11%, battery is ok with 16.17