8th gen kindle stuck on battery icon (!), no reaction to PC

[eddie.t.h]

Honestly, I just got a little stupid. The PMIC documentation says 30mOhm but the marking would point to 3 Ohm. Unfortunately, I do not have a this Kindle to check.
Regarding the serial port, check the jailbreak threads. There is everything about it. A regular terminal, such as putty, is enough.

[WLA80]

Originally Posted by eddie.t.h

Honestly, I just got a little stupid. The PMIC documentation says 30mOhm but the marking would point to 3 Ohm. Unfortunately, I do not have a this Kindle to check.
Regarding the serial port, check the jailbreak threads. There is everything about it. A regular terminal, such as putty, is enough.

Thanks for all the info. I'll try my luck with 3ohm.
As for putty and jailbreak I'm not overly experienced. Can you point me in a right direction, a verified / full-proof thread where I can get info I need?
Cheers

[hius07]

Serial port operations are similar
Voyage
https://www.mobileread.com/forums/sh....php?p=3137590
PW3
https://www.mobileread.com/forums/sh...96#post4010696
some details on KT3
https://www.mobileread.com/forums/sh...d.php?t=293870

[Fibogreg]

It is 30mOhm not 3Ohms because its marking is R030 Not 3R0

[WLA80]

Thread is quite old by now and after a longer break I managed to squeeze some time to get back to the repair.
I have some progress, as I managed to get the com working (using Tera Term / windows) and got a boot feedback as follows:

CPU: Freescale i.MX6SL rev1.3 at 792 MHz
CPU: Temperature 30 C, calibration data: 0x5794fa5f
Reset cause: POR
FRED::: EXTCSD177=0, 179=48FSL_SDHC: 0, FSL_SDHC: 1, FSL _SDHC: 2
Board: Heisenberg
Board Id: P0011807xxxxxx
S/N: G000KAxxxxxx
I2C: ready
DRAM: MR5=0x6,MR6=0x3 512 MiB

So it is the Kindle 8 / KT3, G000KA .
Now for the next step; I've seen on this forum several threads and software / firmware sources, but as I'm not a specialist here, what would be the clear and fool-proof sequence of steps to get it working? I do not need any special features or jailbreak (unless necessary), just a plain, working thing.
Thanks for all the help given this far!
Cheers

[WLA80]

Anyone? All help would be appreciated.
Cheers

[katadelos]

Originally Posted by WLA80

Thread is quite old by now and after a longer break I managed to squeeze some time to get back to the repair.
I have some progress, as I managed to get the com working (using Tera Term / windows) and got a boot feedback as follows:

CPU: Freescale i.MX6SL rev1.3 at 792 MHz
CPU: Temperature 30 C, calibration data: 0x5794fa5f
Reset cause: POR
FRED::: EXTCSD177=0, 179=48FSL_SDHC: 0, FSL_SDHC: 1, FSL _SDHC: 2
Board: Heisenberg
Board Id: P0011807xxxxxx
S/N: G000KAxxxxxx
I2C: ready
DRAM: MR5=0x6,MR6=0x3 512 MiB

Not enough info here to diagnose, we'd need to see the entire serial log (in particular, how far into the boot process the device gets before bailing) before we can help you further

[eddie.t.h]

I had a case like this once. Booting was interrupted right after the CPU boot messages. Flash memory reballing helped. Unfortunately to do it you have to remove display from the board and it is extremely difficult task.

[WLA80]

Originally Posted by katadelos

Not enough info here to diagnose, we'd need to see the entire serial log (in particular, how far into the boot process the device gets before bailing) before we can help you further

That is all listing I'm getting; is there another log I can get?
As far as external symptoms go, it's stuck on empty icon and does not respond to USB (not being detected by Windows). The LED responds to power button long presses, but in a weird way (as described earlier).

[WLA80]

Originally Posted by eddie.t.h

I had a case like this once. Booting was interrupted right after the CPU boot messages. Flash memory reballing helped. Unfortunately to do it you have to remove display from the board and it is extremely difficult task.

Is there no way to do it with the serial as I connected already?

[eddie.t.h]

Originally Posted by WLA80

Is there no way to do it with the serial as I connected already?

Uboot does not boot properly so afaik you can't do anything programmatically. It looks like there is no communication with RAM. In this model RAM is in one chip with flash memory.

[WLA80]

Originally Posted by eddie.t.h

Uboot does not boot properly so afaik you can't do anything programmatically. It looks like there is no communication with RAM. In this model RAM is in one chip with flash memory.

"Reset cause: POR" Sounds like a generic hardware reset.
"FSL_SDHC" - lines refer to emmc / other memory, right?
It does respond to serial terminal, so I'd assume RAM works...

If not by programming, what would be the options?

As for removing the screen sounds to me not difficult, but rather next to impossible as it's embedded onto the pcb. Since all active components are on the backside, would be the exact purpose?

I have a hot air station and I was doing okay pretty much everything other than BGA...

[eddie.t.h]

The processor has its small amount of memory to run the uboot. How would it know how much RAM it has and how connected?
Removing the display is necessary to solder anything on this board, otherwise you will damage the display with temperature. You can cut the display with thin molybdenum wire but it requires extreme patience.
If you have no experience with BGA, maybe this is an opportunity to gain some :-). Soldering BGA in comparison to disassembling this display is a piece of cake.

[WLA80]

Originally Posted by eddie.t.h

Soldering BGA in comparison to disassembling this display is a piece of cake.

so that horror would be a lesser pain than the shitstorm / aka display removal ...
Even being a huge advocate of repairs and saving broken junk, that little piece may be a bit over my head.
Last thing I'd try is to attempt flashing (if at all possible) in a hope that the corrupt log/listing results from some other code issue. Any idea how to try forcing it?
Otherwise I think I'd call it a day for that one...

[eddie.t.h]

Unfortunately, as I have written before, this is one of the worst Kindle's to repair.
See this https://www.mobileread.com/forums/sh...d.php?t=327055 thread but I've never tried it so I don't know if it works.