Watch shuts down during exercise

I really don’t see how it’s a Covid tracking issue.

I rode today but took my phone too. Left WiFi and Cellular data turned on and everything worked fine.

The issue is the watch beaconing out for a connection to something and draining the battery. It’s like a cellphone battery drains much faster when you’re in an area with poor or intermittent cell coverage.

I started noticing this too a few months ago when I was working out. Once I accidentally hit my watch because it was being unresponsive, Now it ALWAYS shut off whenever I hit the side where the speaker is on for some reason??

I sent it sent it to Apple to see if they can replace/repair it but they sent it right back saying there was no problem. This is really strange especially because I had the original apple watch from 2015 and used it for 4 years with no problems at all.

As a theory what you lay out sounds about right except 1. New watches having same experience 2. Watch has substantial charge left after shutting down. I think it is the demand of the “contact tracing IOS” installed in the latest updates. As long as you are not working out, you will not have seen any differences in the IOS.

If it is an iOS problem, wouldn’t it be more widespread? It seems like on a small number of people are reporting it.

I’ve had the problem for about a month, so before the latest update. And I don’t believe I have had any Covid app loaded.

I updated to WatchOS 7 and got a new problem where Workout GPS maps stopped working! Had to unpair/re-pair watch to iPhone which seems to have fixed it. There’s a new topic been started about it.

One thing I did notice is that battery life seems better though, although that might be just optimism!!

Today I updated my Cellular enabled Watch 3 to OS7, did a 5 mile run with Power Saving Mode on (no cellular) and it worked fine. Couldn't receive a call or texts, etc., so still not meeting my expectations, but I was able to finish the run and listen to a playlist that was on the watch.

Did it again with Power Saving Mode off (cellular on). This was the only change (other than running slower cause, well, I had just run so..) About 20 mins into the run..... Watch shut down. Same problem, so OS7 didn't fix it. For you power aficionados out there; the watch battery was about 70%, headset was about 80%.

Very disappointing.

When you turned the cellular back on, you increased the drain on the battery. The increased drain caused the voltage to drop below minimum operating level, and then the watch crashes. The fact that the battery still shows a 70% charge is meaningless. The power management algorithm still thinks the battery has a charge, which it does, but the battery voltage is breaking down under higher load. This is a common symptom of a Li ion battery going bad. My Apple Watch 2 will go about 90 minutes in exercise mode before crashing. I actually happened to catch it in the act of crashing last week, and the battery screen flashed “low battery” mode for a couple of seconds before completely blanking, indicating that the power management software detected the problem before the voltage really tanked. When I restarted the watch, it showed 50% charge, but was no longer able to operate in exercise mode, so the indicated charge level is not a good indicator of battery health. These batteries last about 3 years. After that, you should expect to have to replace them. They do not always degrade gradually and gracefully.

i do not believe it his is an OS problem. Changes in the os may have increased the battery current draw, thereby exacerbating the issue, but it is very unlikely that the os itself is the root cause. .

Plausible, but in this case I don’t agree. Battery health is at 95%, the battery is fine. Also remember that many of us began to experience this immediately after a specific update. Faulty algorithm is more likely.

The battery health indicator is not relevant in this situation. It tells nothing about the battery misbehavior under high discharge rate.

The only way to know for sure is if someone shells out the $79 to have the battery replaced and see whether the problem goes away.

I have been following this thread for a month or so as my 44mm series 4 cellular watch was doing the same thing, shutting down when out on a run (I use the Nike Run Club app).

I do really like your theory about battery voltage draw however I’m confused because to get my watch to not crash, I had to turn off both cellular and WiFi and it was fine for a month or more, since I cancelled my cellular plan with EE I can run with WiFi on and it doesn’t crash, I just have no cellular coverage. I’ve always ran with my AirPods connected and music playing so recently surely my battery drain has increased and no crashes?

Effectively I have a cellular watch acting like a WiFi / gps watch.

Same problem here, seems unfair, especially since we are still paying the monthly cellular fee. Regarding what is happening with Ryan's device: this makes sense to me since the LTE (cellular) radio pulls significantly more current than wi-fi module when transmitting, so the drain is higher. This is why the battery lasts much longer when LTE is off. But, I think that the first few versions of the watch (maybe 2 &3) are what we call "bleeding edge" technology, and were rushed to market too soon since the LTE battery life was pretty bad even when new (anyone have this problem with Version 4 or later?). What I acknowledge, but don't fully agree with, is that this is the only problem. I believe we have a compound issue; hardware and firmware/software problems combining to cause the failure. I think there is something wrong with the way the watch calculates power reserve (or rate of power drain), because it kills it too quickly while there is still a lot of power left, while the battery health is still quite good. I am not familiar with the particular algorithm that Apple uses to calculate this, and some helpful speculation has been made in this thread, but we don't really know and they will never tell us because it's proprietary. We do know that Apple has gotten very good at understanding the rates of power drain on their devices, but we don't know how much of that was implemented and how accurate it was in the earlier LTE Watches. But again, proof of this was not solely a hardware problem is that the change happened abruptly for many of us earlier this year after an update. After the update, if you got unlucky and had the right (or wrong) combination of things happening at the same time, the watch shuts down. It's possible that the problem is too complex to troubleshoot and will never be resolved, especially after Apple care determines there is nothing wrong with any of it, which was the case for me. And yet it happens.....

It is possible that the software update somehow increased the current draw on the battery under certain conditions, thereby revealing an underlying problem with a marginal battery. I am not in love with my own idea, but the symptoms do suggest to me a battery problem. It is possible that the battery health indicator can indicate plenty of charge remaining in the battery, but under the stress of high current demand, the battery voltage breaks down in a sudden way that doesn't give the watch enough time to execute battery warning and graceful shutdown. Such a breakdown is like throwing a switch and having the power suddenly cut off. I have seen iPhone batteries fail with very similar behavior (sudden crash), with the problem corrected after I had the battery replaced.

If you watch is 3 years or more old, you should be thinking that the battery is well into its expected useful life and is probably in need of a replacement. If your watch is less than a year old and having this problem, I think you should demand that Apple replace the battery under warranty.

Im in same situation and maybe just a coincidence but I only had this issue after signing upto cellular data again.

people running non cellular models kinda rule this out.

But on the flip side, watch has been fine when just turning WiFi off.

So pleased I’m not the only one with this issue!

The current draw of a watch that is just being passively worn is much lower than a watch that is monitoring a workout and taking heart rate measurements by turning on the lights on the back of the watch.