Bangle JS 2 won't connect via Bluetooth after full charge

[eve-nisse]

Watch was working fine for years before full charge, then disconnected and wouldn't reconnect to Gadgetbridge.
Now shows up in discoverable devices on Gadgetbridge and Android, but doesn't finish pairing or connecting when initiated.
IIRC it should ask for confirmation on the watch or work after a few tries / few seconds.
Bluetooth icon in top right corner is grey remains after turning BLE off. (edit for clarification)
Tried restarting phone and watch, re-installing GB and factory resetting the watch, different settings.

Edit. Trying to re-flash the firmware in DFU mode also results in a quick BT connect and disconnect.

[thyttan]

This sounds like what I experienced for some time now. I've written it up in some comments here: #7789 (comment)

I have still not found a permanent solution.

Please read through and say what's similar and different to your problem 🙏

Sometimes I could fix the problem by visiting the recovery menu by pressing and holding the HW button, or by reflashing firmware once/multiple times. But nothing's been 100% reliable every time...

Can you provide info on your:

• phone model
• Android version
• Gadgetbridge version
• Bangle.js firmware version
• do you connect the watch to other devices besides the phone?
• can you think of anything you did differently from usual before the problem manifested for you?

[thyttan]

Are you still unable to pair @EverardNisse? If so maybe we could ask you to provide Gordon with a backup of your watch?

[thyttan]

I woke up and the watch had the pairing problem again - I sent you an email with the backup @gfwilliams 👍🙏

[thyttan]

1. Bangle.js 2 unpaired and unable to pair again with phone.
2. Enter recovery menu by press and hold HW Button.
3. Chose factory reset.
4. Diaable auto reconnect to device in Gadgetbridge.
5. Once booted and on clock face try to connect without success.
6. Visit Bangle Bluetooth settings and make connectable just to make sure.
7. Try to connect again w/o success.
8. Fully disable and force close Gadgetbridge.
9. Try to connect without success.
10. Hold HW button to cycle to and through the recovery menu until ending up on it once more. Release button.
11. Hold HW button again untill >bluetooth message shows at bottom, then release button.
12. Now back on clock face, try to connect again - SUCCESS!

So still uncertain on what are the requirements for the successful outcome.

Next time I will start with double cycling though the recovery menu by continue to hold the HW button.

[thyttan]

It just happened again and this time I saw it happen. Ca 18:30 in the logs (I'll email them to you Gordon).

1. I was installing BMO Face app (testing a PR) via personal app loader inside Gadgetbridge.
2. As the progress bar neared compleation (ca 95 %) the watch spontaneously rebooted itself.
3. Immediately the pairing request notification was presented on the watch.
4. Before interacting with the notification I went to Gadgetbridge to disable some reconnection logic (I think GB had already connected to the watch again).
5. I disconnected Gadgetbridge from the watch.
6. I then said "Yes" on the notfication to pair with the Bangle.
7. Checking in Android Bluetooth settings the pairing had not been successful.
8. I tried to pair from the Android Bluetooth settings also w/o success.
9. fetch GB log.
10. Hold HW button cycling to the recovery menu twice before going back to clock face.
11. Try to connect (pair) without success.
12. Disable Gadgetbridge fully and toggle airplane mode on/off.
13. Try to connect without success.
14. visit Bangle bluetooth settings "Make connectable".
15. try to connect without success.
16. Go to recovery menu and do a factory reset.
17. Once on clock face - try to connect without success.
18. Hold HW button double cycling trough the recovery menu. Exit to clock face.
19. Try to connect - SUCCESS!

So the combination of:
a) disable Gadgetbridge fully.
b) Do factory reset (from recovery menu)
c) subsequently double cycle through the recovery menu.

... seems to be what does it. I suspect step (a) may not be needed. I'll try to investigate that next time maybe.

It would have been intreseting to see what would have happened if at step 3 I had answered "Yes" ASAP.

---

Line 16746 in the log seems to be just around when the watch rebooted spontaneously, with GATT_INSUFFICIENT_AUTHORIZATION. Not sure it was before or after the reboot.

Before that the log shows the BMO clock face in progress of being loaded to the watch with GATT_SUCCESS messages.

The line in question:

18:30:12.793 [BtLEQueue_0_in] DEBUG n.f.g.s.b.BtLEQueue - connection state changed: STATE_DISCONNECTED GATT_INSUFFICIENT_AUTHORIZATION BOND_BONDED

We get an ACL_CONNECTED on line 16794:

18:30:21.999 [main] DEBUG n.f.g.e.BluetoothConnectReceiver - observed device D6:92:EF:02:3B:01 via ACL_CONNECTED

We still have BOND_BONDED though. It is not until line 16920 we get the first BOND_NONE:

18:30:55.664 [BtLEQueue_0_in] DEBUG n.f.g.s.b.BtLEQueue - connection state changed: STATE_DISCONNECTED GATT_CONN_TERMINATE_LOCAL_HOST BOND_NONE

---

[eve-nisse]

Please can you try restarting the Bangle, holding the button all the way to the recovery menu (and then a few more seconds)?

Bangle.js will clear out any saved pairing data when it's started up with the button held down, so that might help - it's possible that even though you managed to enter recovery, the button wasn't held quite enough to clear the pairing data.

Have you tried connecting from any other devices, like a PC or a different phone? Is the connection there stable?

I've tried restarting, recovery menu, double recovery menu, DFU mode, holding the button a much longer time, running the battery down, connecting to other device, re-flashing, etc, they all fail. The suggestions here from the other peeps have no effect. Only things left are firmware (driver) and hardware failure it seems

edit: if there's a way to flash via cable, some pointers would be helpful

[eve-nisse]

It took a week for the watch battery to empty ofc, and booting it now it still has the BT icon always on grey (edit for clarification), shows up in BT pairing, does not pair ever and does not accept firmware flash.

[eve-nisse]

Aha so it will empty the battery, got it.
I've tried another phone, 3 PCs with different OSs. Other BT connections don't have issues

[gfwilliams]

Ok, thanks - that's not looking good then. How long have you had it?

[RKBoss6]

Have you tried forgetting and repairing the watch to your phone? That usually works for me if I have any connection issues.

[eve-nisse]

Yes, it was still paired on the phone when it stopped getting notifications.
After unpairing in the Android BT menu, it's also refusing to pair there.

Ok, thanks - that's not looking good then. How long have you had it?

It's been 3 years of everyday use. I'm betting on hardware issue or firmware issue possibly solvable if the battery is disconnected. Might try to open it up and poke around

[gfwilliams]

Ok, that's strange. Although being paired in the Android BT menu could likely have caused your issues connecting with other devices.

or firmware issue possibly solvable if the battery is disconnected.

I'm pretty certain that as far as Bluetooth is concerned there's no real difference between a long-press (~10s) reboot and disconnecting the battery - but you can definitely try flattening the battery which will have the same effect (there's an option the Settings->Utils to increase power draw to get it done more quickly).

If it is a hardware problem, you might find that squeezing the rear hard in the top right corner (viewed from the front) of the watch may help. That's where the connection to the aerial is, so if there was some kind of oxide layer there, repeated movement might help to break through it and make the connection more reliable