Originally Posted by geekmaster
If it is not the battery, then maybe you have a bad USB cable, or a bad USB port on your computer. Try plugging it into a different USB port. Try a different USB cable. Try a different host PC. To test you computer, you could try a different kindle.
It is possible that your kindle has its copy u-boot bist image damaged in mcc so that fastboot cannot work without reflashing your mmc. This can be done with MfgTool and different profiles (that need to be created), which will work even with a completely erased mmc, which is how it is flashed the first time at the factory.
We could do that too if we had a complete firwmare image to flash to the empty mmc. What we can do now is flash images of individual firmware partitions, but there are protected areas that appear to be write only and read as zeros in user-land programs (like dd), so backups of those areas (like the first 32MB of mmcblk0) may be incomplete, and flashing them to mmc may overwrite good hidden data with zeros (bad). You need to be in kernel mode (or in u-boot), to read those areas of mmc. This concept of "write-only" areas of mmc was proposed by yifanlu, and it makes sense to me based on evidence that I have seen.
Fastboot will allow you to erase the entire mmc. I strongly recommend that you do NOT do that.
It is also possible that your kindle hardware has failed, in which case a replacement kindle is your best option.
Thanks for your help again.
And I've changed different pc and laptops, also from windows, mac to linux, still no luck. Different USB cables from different brands were also being used.
Probably, the u-boot bist image is damaged, or it's the hardware issue that nothing I can do now, so I'm sending it back to Amazon, sigh...
Anyway, it's very appreciated for your kindly help, and I benefit a lot. Excellect work! Cheers!