Battery draining quickly when updating firmware to ver 13.0 ?

Hello there!

after a couple of month sending emails to my nearby Garmin service (which were suggested by Garmin Support ) and they didn't bother answering me, I decided to tackle with my own problem and started various Disable-Enable on my watch till I let my watch to go under 5% which is considered as "Critical Low" by the watch. and opened the Navigation app on Watch and searched for GPS inside the room to see if it can recognize the coordination -which it didn't- but after that I charged around 3 % to fully charged and it has been 2 weeks from that day which stopped draining battery.

It seems to be somehow a mix of hardware and softwar Issue which wouldn't be get fixed even with a Hard-Reset or Another new Update !

The watch stucks into searching for GPS and it acts in nomal watch mode as its during a Navigation usage even though you haven't selected. (AT LEAST FOR ME!)

Let me know if you tried this and worked for any of you.

Peace

My Garmin 945 watch started to discharge in one day, also coincidently after updating to ver 13.0,  tried a hard reset (didn't try GPS restart only like Mehrun mentioned)
So I've given them to the service center. They said that the power controller had a damaged element (they saw excessive heating in the thermal imager) 
After the power controller replacement, the battery lasts for more than a week without tracking activities. As a downside, I'm not recommended to swim in them because case was opened and re-glued by the service center.
I have used my watch for more than four years, and as I see on forums some garmin watches battery drains are caused by hardware issues.

pikabu  .ru/story/garmin_fenix_5_plus_byistro_razryazhayutsya_9164342

or this drainage caused by failed sensor hub
remphone .ru/remont-chasov/casi-garmin/garmin-fenix-6x-sapphire/garmin-fenix-6x-sapphire-artefakty-na-izobrazhenii-i-postoyanno-perezagruzhayutsya

So for the last few days I’ve been testing the battery on my 945 and there appears to be a consistent 10% drain every two hours. For example, if I charge the watch to 100% at 5pm, it’ll be at 90% by 7pm. And so on until it shuts off. It’s ridiculous for a watch of this caliber. The battery drain is literally the only problem with the watch. I’m considering sending it back but I wonder if the problem is the last update. 

UPDATE:

since last time I tried to observe battery drain several time and it seems to get stable. and despite a couple of month which battery used to get charged and drain the battry health seem Good.

the screenshot below shows my activity within 10 days from fully charge until 13% considering ( 4 acitivity X 30 minute )  can be seen in every sudden drop of battery spectrum.

current watch settings : ( wifi:off  / activity-tracking:off / SPO2 sensor:off / Gesture control: off / bluetooth : on / notification: on / HR-monitor: on )

but overal it seems Garmin is not doing any updates anymore for the 945?

Can anyone tell what fixed the battery drain on the 13 software for some people? Or how you revert to version 11 or something?

My battery hugely improved by disabling Smart Notifications (overall, during and outside activities) and setting Pulse Ox only to sleep.

I forgot to mention that my watch is on Ver. 13 and seems there is no furthur update. it must be a software bug which puts watch in a situation like seraching for gps signal even after a factory reset. but i'm not sure if everyone facing this problem, can overcome this problem or not.

Hi there. Did you get any help ? My watch forerunner 13 suddenly now drain the battery . Have no idea what cause that !?

Hi. 

Last couple of days my watch just draining battery in one day ! The settings are the same and I have not really changed anything. Did anyone experienced similar issue ? Perhaps new software or something? When I checked I have ver 13.00