Battery charges only if watch is off

I have replaced the battery of my Lemfo Lem 8 for problems already explained in a previous post.

Now the watch works well again, battery lasts as it did before, but when I put the watch under charge, if it is on, the battery keeps draining, while if the watch is off, it regularly charges in around half an hour (it absorbs 1 A and its capacity is 500 mAh).
I have never seen this behaviour before replacement.

What could it be?

I’ve only seen this with the Rollme S08 which stays Always ON when charging and then only discharge if you don’t turn off the display… But in your case the screen is not even ON and you need to shut it down ? That’s weird.

Indeed. And it didn’t behave like this before, so I suspect it’s a software problem. But before resetting or flashing a firmware, and having to setting everything up again, I would like to know if there’s something I can do.

I’ve checked, when the watch is on and under charge (verified by the icon on the watch and a tester) the display turns off, but battery gets overheated, until a message shows telling battery temperature is too high and I should remove the battery! And battery level keeps decreasing. On the contrary, with the watch off, charging performs regularly and battery stays cold.

i have seen this before. when I tried to replace my finow Q1 battery with some cheap mp3 player. The battery overheats and doesn’t want to be charged when the watch on, because different battery controller (pcb in the battery) and only can charge when turned off.
So the solution is replace the battery pcb with the one in the original battery, or just charge the watch when it’s off.


Thank you. If this is the case, I’m quite disappointed, as I purchased the replacement battery from the watch seller, so I thought it was a fully compatible battery.

this always happen at chinese product AFAIK, since different batches have different things too. Like few component replaced with cheaper ones. even in finow q1 era, when the earlier batches have 1+8, later batches have 512+4. that’s terrible in sense, even if later batches is cheaper than earlier batches. the fault in the supplier or maker.
Well, the point is at least for me better to buy new ones when the older have problem especially chinese product since it’s easier that way (time and money wise). and I still have all my FAW still in good condition mostly with all of them have dead battery.