Disappointed in the battery drain during my marathon...

I ran an ultra with time of 9:45 using the older firmware in June, had a chest HR monitor & a Stryd footpod connected all the way & it went from 100% to 10% by the end. Think the new firmware is definitely worse battery-wise.

First off - good luck in the TCS NYC Marathon and enjoy NYC.  If you are on the lower level of the Verrazzano stay away from the outside lanes.

As far as your FR 645, have you tried a hard reset?  Both my wife was has a VA3 and I (FR 646M) have occasional problems with battery drains and hard resets seems to resolve the issue for us. This might not solve your issue, but it is worth a try.

Good luck...

I normally worked on +- 8% / h, proven on a 11h ultra, GPS only.  (v4.20)

The other day I tested GPS + GLONASS (v6.20) - starting a run with 15% battery and it shut down after approx 40 mins :(   

Nighthawk700First, congratulations on your marathon and good luck in New York!

The battery life you're describing is definitely concerning and should be occurring. I realize this is a simple troubleshooting step that you may have done, but I would recommend you start with a hard reset (hold power button down for 15 seconds, then power back on). 

This shouldn't be necessary under normal circumstances but it can resolve strange issues like the one you're describing. If this is not successful, we would want to look at any connect IQ items you may have recently installed or other settings changes that might have occurred. 

So to answer the posts so far (and thank you all for your comments and congrats):  I thought I did do a hard reset, but will try to do so again.  As for recently installed Connect IQ apps, I haven't added anything new for several months now.  However, there have been a lot of updates in the existing apps because of the new firmware.  I'm actually thinking of removing several of the apps that I rarely use.  I hadn't removed before because I remember in the early days of the 645 there was an issue where if you removed an app, it also removed the Run app, which is the key thing I need my watch for!!  Plus I am using less than half my available app space, so didn't think it would be an issue. 

I have a half marathon I'm doing "for fun" (e.g. easy pace) with my daughter halfway between the Wineglass and NYC, so that'll give me a chance to test how the watch is working, and even if there is a high battery drain, it shouldn't run out by the end of the half.  If things are better (I hope!) then I can leave the HRM on for the full.  If not, then it gets shut down the morning of the full.  And I did also submit this issue to Garmin Support, so I'll see if anything comes from that channel. 

Garmin email support's answer.  I'll try it along with everything else.  

Thank you for contacting Garmin - happy to help! 

Sounds like you have a corrupt file on the device somewhere. Try these steps: 

• Connect the device to the computer
• Located the drive folder (it should show up in the same spot as a USB stick)
• Locate the Garmin folder
• Under the Garmin folder, locate the, ACTIVITY, REMOTESW, NEW FILES and MONITOR folders
• Be sure your Garmin Connect account is up to date with your last activity as this will delete the data on the device.
• We will want to delete those four folders (the entire folder not just the stuff inside).
• Empty the trashcan/recycling bin on the desktop
• Unplug the device
• Power off the device
• Power it back on

If you still see issues after this, let us know and we can go from there. 

FYI I've done 2 hard resets (where I had to reconfigure everything from scratch) and it did nothing for my battery drain issue. This has only occurred since loading 6.2.  I hope you have better luck. 

Well, I did both what Garmin-Blake said, as well as the email tech support.  The result was after I finished a half marathon (Hershey) today, I had 78% battery remaining.  Much better.  I feel more confident about using the watch for NYC, although I'm sure I'll be glancing at the battery life more often than I normally would, to make sure.  Thanks.  

Hi finished my marathon on Sunday 3:55 with chest strap and battery went from 100% to 68%(latest updates and gps+galileo).  Just to compare  

Hi, ran marathon on Saturday, FR 645M, fw 6.2, HR sensor on,  GPS only, no music playback during race. Finished in 3:40, battery consumption 35%.