There could be several things:
- the SD card got corrupted somehow, please reflash it
- the SD card was not fully inserted, please see pics at
http://jevois.org/doc/UserStartWindows.html
- other than that, it might be some physical damage to the camera. If you have a USB-to-serial converter, you can try to enable verbose boot mode and see where it fails:
See "Debugging the boot process on platform hardware" at
http://jevois.org/doc/Debugging.html - in your case just edit uEnv.txt on the BOOT partition of your microSD and comment out the quiet boot, then uncomment the verbose boot. When JeVois starts, you should see standard Linux boot up messages like shown at the bottom of that Debugging page.