i'm experiencing some problmems with my Arduino 101. The BLE module seems to be not working if i power the Arduino with a 9V battery over the power jack or the power pins. However, it sometimes works, but i don't know what is diffrent, while it works. Even pressing the reset buttons multiple times doesn't help. Powered by a USB-Cable everything works fine everytime.
Do i need to update the firmware or something (if thats the case..wich firmware?) ?
A regular 9 volt battery has a very short life on most Arduinos and is only really useful for short tests.
There was a 101 update but I suspect that would not help in this situation.
It is clear from your question that the power supplied by the USB is enough to keep it going as it is a constant current / voltage source unlike the battery which drains too quickly.
A better external source such as a LiPo or other rechargeable heavier duty battery would by my first choice.
a use a rechargeable for test with arduino 101 it works fine, check regulator circuit (TPS62153RGT) maybe it's not working properly. check arduino 101 schematics if you want to replace it, but i suggest another power source, i prefered to use a Li ion batery with a boost converter (to 5V).