What does the Power LED's displays mean?

The LED indicates the status of the power-on and upgrade.

a. The red light is on while powering on the camera and entering system.  If the camera is successfully turned on, the red light will turn off, if not, the red light will stay on.

b.  If the light flashes blue three times while powering-on, that means the camera has entered the firmware update mode.  If the SD card has a firmware update, the blue light flashes. If the SD card does not have a firmware update, the LED shows a steady blue light, while waiting for the update to be inserted in SD card.

c. If an update is in progress, the state of the LED is as follows:
1) Flashing blue light means the update is happening with no issues.
2) Flashing red light means the firmware update is not compatible with the current hardware.
3) Two red flashes means the update file contains an error, usually CRC error.
4) Three red flashes means version number check failed.

d. If the LED light is off or shows purple after powering up, it means BLD did not start properly. This may be due to hardware, battery, or loss of BLD.