Tips to fix Charge 5 blank screen and battery drain

[weljj]

Looking for a solution to the charge 5 black screen or battery drain w/o access to the source code is very difficult, to say the least. (I think because of the ECG function there is good reason not to share the source code)

Having a little experience with software-hardware interfaces, I really suspect the fundamental issue for battery drain is the fitbit gets stuck in an infinite loop polling some part of the hardware (calculation of time, hitting the bluetooth connection to the phone?) That poll process is using a lot of battery power and drains the battery, ultimately causing a blank screen or related issues.
---

I posted what worked for me (unpairing, forgetting the bluetooth, do the fitbit reset using charging cable 3 button push).

But, then @RiekoC also posted that doing the fitbit reset multiple times worked, which was something I had done before my "final" solution. So it might have been coincidence that my final attempt could have worked just as well without the bluetooth unpairing.

Why would changing the clockface fix the problem -- perhaps changing the clockface also purges a cache with bad data on the charge 5?

Compounding the problem is the app on the phone could be the source of the problem, somehow altering the data on the charge 5 that then causes the issue.
---

Users are reporting problems, but they don't also supply the firmware version because they don't know it would be helpful.

Realistically reporting their particular configuration of fitbit functions they use would be very difficult to do in a message board format.

It would be *really nice* if the message board allowed for sticky posts, so the very first post a user sees is always "How to report a problem" which would say provide your version number, phone type, version of the app.
---

What would be a good first step, I think, is for specific firmware version(s), create a reliable method that got the charge 5 working in a "bare bones" mode. By bare bones I mean all of the extra tracking and statistics are completely turned off, so the charge 5 is only displaying the time, and the functions that are normally on when the fitbit is initially setup for the very first time when it came out of the box and there was no app on the phone.

There appears to be no way to do a true factory reset -- where all user data is cleared AND the firmware rolls back to the version that was installed when the charge 5 came out of the box. Someone correct me if I'm wrong about this, does the firmware roll back or not when the "clear user data" function is completed on the charge 5?
---

A trial method might be:

1) Remove the fitbit app from the phone
2) Clear the fitbit app cache on the phone
3) Unpair/forget the bluetooth connection for the charge 5
4) If there is a black screen or low battery level, put the charge 5 on the charger and charge to at least 20% (30%, 40% ?)
5) On the charge 5 -- from the device perform "clear user data" function (Settings->Device Info->Clear User Data)
6) Now complete the normal setup, (the clockface should be the default face).
7) Do NOT enable any other functions yet.

If after these steps the charge 5 is operating normally for a few days (or not), then the user reports back with their version number, phone type (android, apple), and that it worked or not. They could then incrementally start adding extra functions or give up.

Perhaps this would get many users back to an acceptable level of functionality for their charge 5

---
I would try this on my own charge 5 but it is currently working fine, and I need the ECG functionality, so I'm not willing to try it unless I have an issue again with my charge 5.

Moderator Edit: Clarified subject

[RiekoC]

Hello @weljj 

Thank you so much for taking the time to share this information. It will be helpful for other users.

I'd be interested in your thoughts about this user's post on how they were able to resolve the flashing logo problem by putting their Charge 5 in the freezer, if you have any insights.

[weljj]

I hope users can ultimately contribute to the knowledge base of how to solve this issue.   It's clearly a software problem, with myriad ways things can interact, which is why we need the simplest, most bare bones restart to get some confidence in the hardware itself.   But without "sticky" or "pinned" posts, this post too will ultimately drop into oblivion...

---

I have only a couple of wild guesses about the freezer trick.

Maybe there is a thermal sensor in the charge 5 that does actually shut it down when the temp is too cold.

or,  (still a wild guess) -- considering the chips are physically designed for operating in a certain temperature range, one of the constraints is that different materials have different thermal expansion coefficients (i.e. plastic may contract less than metal as it gets cold).  So if metal contracts enough more than the substrate it sits on, then it could physically break an electrical connection somewhere in the system, sort of like powering the device off even though there is no power off switch.

---

The manual states it can operate in the 14 to 113F range, and be stored as low as -4F.  I just looked up, and see it is recommended that freezer temperatures be about 0F, so I'd be concerned about actually damaging the charge 5 in the freezer.  I'll bet some freezers are set below -4F, and some charge 5s will also probably be damaged at temps just a littler higher than -4F.   Seems like one thing quality control at the factory would not be checking on individual units is do they survive storage at exactly -4F.

But if your charge 5 is really "stuck", and you've already tried a bunch of resets, it may be time for the freezer since you've nothing to lose...

Thanks for responding to my post, and, being so helpful to users that come here with problems.

[RiekoC]

Hi @weljj 

Thank you again for taking the time to provide such good detailed, easy to understand insight.

We definitely appreciate having users like you who are also trying to help our users with their issues.