unable to Boot From SD card

I had my beagle bone black, which used to boot from my custom u-boot and kernel. But now, It is unable to boot from the SD card for no apparent reason.
The SD card is fine as I can mount ,read and modify files in the partition.


  1. SD card readable via a SD card reader over USB.
  2. Boot flags set by gparted on the boot partition containing MLO and u-boot.img
  3. no “ccccccc” messages over serial connection. emmc is being used as a boot source. I can make that out as I get a prompt even when I do not have a rootfs on my SD card also I had kernel 3.10 compiled I get a 3.8 kernel now…
  4. USER LED 1 is not blinking. USER LED 0,2 are the one that are active.

can it be a fault with my switch S2 ? should I try to short the lines on boot to create a switch press action ?