When your Blinks Dev-Kits first arrive, each of the Blinks have been programmed with a simple validation sketch found here.*
Blinks are set to go to sleep after 10 minutes of inactivity (i.e. no button press) and if they go to sleep while their button is pressed down, they prevent themselves from draining a bunch of battery by disabling the button (this is the case for the current github master firmware). To get your Blink to turn back on, there are 3 easy ways to do so.
- Unscrew and then screw in the battery. this power cycle will get it up and running again (Note the screw is a #00 Philips)
- Plug in your programmer and reprogram the Blink
- Jump start the Blink by touching a metal object to the screw and the reset pin on the ISP. (With the screw above the ISP pads, you would touch the metal to the bottom left pad and the screw)
I find #3 to be the quickest, and it makes for a fun party trick in the process 
If you think the battery is actually dead, we’d love to know. The 3.3v Lithium CR2032s will happily power the Blinks until they are below 2.5v and the battery should spend most of its life around 2.8-3.0v. Using a multimeter to check the battery is the most reliable way to measure this.
*The sketch does the following, rotate red, green, blue to validate the RGB LEDs, when the button is pressed they should show white, and switch to communication mode. When in communication mode, they are dark and neighbors flash cyan and magenta to show sending of 1’s and 0’s.
