Bangle Js black screen

Hello @Guillaume_G well that was worth a shot. As the Holiday is upon us, it might be that there will be lower viewer visibility within the forum this weekend. It might make sense to provide more detail in the steps taken so far, Kickstarter or new model, version if known, and what application was running, if your own, what general activities were underway, such as how often GPS reads, method to store and how often etc., along with how long the device was on, what reset sequences have been tried, double checking the charger cable direction, what exactly is seen, text msgs and so on, so that the next individual might be able to better assess using reverse logic elimination.

In my case, having bizarre charging experiences with LiPo in general, I made the assumption that the charging circuitry wasn't detecting a sufficient voltage within the detectable range to actually start the charging process. LiPo requires a stable state for constant current charging. So, if this is the case with your Bangle also, it might be that additional current draining is required or maybe a slight charging current trickle boosts the voltage just enough for the charging circuit to get started. Mine sat for several weeks, while yours was indeed operational. There must be some commonality that will get yours running again.

Just had a thought, if this were an app that was executing, is it stuck in a loop waiting for a specific keypress even though that feedback content isn't viewable on the black screen. Maybe holding down that known button might allow the app to adavance sufficient enough to then use one of the reset methods.