Originally Posted by nikoday
My k4 black was bricked after one month use.
I followed the instructions in ‘ Guide to debricking Kindle Touch v4’ ， but got stuck when entering diags mode.
I used the images from pastebin, flashed all 3 images including diags, diags_kernel and kernel, but got black screen when entering diags mode.
I guess maybe these images are NOT suitable for k4 black?
Both K4 colors use the same firmware. It should work.
Which images did you download?
What commands did you use to flash them?
Did the images get flashed to the correct locations?
A black screen could happen if you flashed the main kernel to the diags_kernel partition...
On the K4, the main partition uses eink drivers (and other code) similar to the K3. But in diags, a K4 uses code similar to the K5. You can verify this by noticing that K4 main uses the eink_fb driver, while k4 diags uses mxc_fb (the new K5 eink driver).
EDIT: Why did you flash "kernel" without its matching main partition? Where did you flash it?