Help debrick Kindle Paperwhite

[KingD]

My Kindle PW stops working several days ago. The device was jailbroken long before. Nothing particular is done recently and I'm using the native reader on that day. I pressed power button to start reading, but the device did not respond immediately. I tried several times before giving up. Minutes later it suddenly shows the content of the book that I last read. It does not respond to anything since then, however, including long pressing the power button.

I first thought it was due to low battery. So I charged it overnight. No luck. Then I took apart the device and gave the battery an full charge. Now it could be recognized on Windows as a USB HID device. I checked several forum posts. It seems that my device is in USB download mode.

I tried with the "simple debricking methods". I used Mfgtool from a Windows 7 guest VM (Mfgtool does not work on my 64bit PC as it always crashes on selecting USB ports). Mfgtool reports success on switching to fastboot, but when I use the fastboot tool, it stuck on "waiting for device". The driver generated by inf-wizard is already installed.

Any clue for this? or maybe it's an hardware issue? The device is already out of warranty. Thanks in advance.

[knc1]

Originally Posted by KingD

My Kindle PW stops working several days ago. The device was jailbroken long before. Nothing particular is done recently and I'm using the native reader on that day. I pressed power button to start reading, but the device did not respond immediately. I tried several times before giving up. Minutes later it suddenly shows the content of the book that I last read. It does not respond to anything since then, however, including long pressing the power button.

I first thought it was due to low battery. So I charged it overnight. No luck. Then I took apart the device and gave the battery an full charge. Now it could be recognized on Windows as a USB HID device. I checked several forum posts. It seems that my device is in USB download mode.

I tried with the "simple debricking methods". I used Mfgtool from a Windows 7 guest VM (Mfgtool does not work on my 64bit PC as it always crashes on selecting USB ports). Mfgtool reports success on switching to fastboot, but when I use the fastboot tool, it stuck on "waiting for device". The driver generated by inf-wizard is already installed.

Any clue for this? or maybe it's an hardware issue? The device is already out of warranty. Thanks in advance.

Without the device in hand, I can only offer a guess -
but a very reasonable guess based on your details.

"I pressed power button to start reading, but the device did not respond immediately."

It was busy with an OTA update.

"I first thought it was due to low battery. So I charged it overnight. No luck. Then I took apart the device and gave the battery an full charge."

Yup - it was a low battery (low storage capacity battery due to age and/or use patterns).
Not enough stored charge to complete the OTA update.

So now your flash chip is corrupted.
https://www.mobileread.com/forums/sho...49&postcount=3
I.E: Your Kindle just "self destructed".

What you see is the firmware's "fall back" response to its inability to load and run the (trashed) firmware image.

[KingD]

Originally Posted by knc1

Without the device in hand, I can only offer a guess -
but a very reasonable guess based on your details.

"I pressed power button to start reading, but the device did not respond immediately."

It was busy with an OTA update.

"I first thought it was due to low battery. So I charged it overnight. No luck. Then I took apart the device and gave the battery an full charge."

Yup - it was a low battery (low storage capacity battery due to age and/or use patterns).
Not enough stored charge to complete the OTA update.

So now your flash chip is corrupted.
https://www.mobileread.com/forums/sho...49&postcount=3
I.E: Your Kindle just "self destructed".

What you see is the firmware's "fall back" response to its inability to load and run the (trashed) firmware image.

Hi knc1,

Thank you for the reply. The device was put in airplane mode for quite some time and at the time it was not in a place with Wi-fi connection. Will it still perform OTA update?

The battery was low but from the system battery icon it could still work for hours.

[NiLuJe]

Unless it's a 3G device, or it downloaded the OTA beforehand.

In any case, in the K5 family, and since FW 5.3, the update format changed, and the code path used to apply it too. The factory updater does a battery level check before proceeding with the update. I've never actually tested it myself, so there's still the possibility of a bug somewhere, but I'd look somewhere else for the initial cause of the issue.

The whole MfgTool mess on Windows has always been awful, which is (partly) why Kubrick was born, so it couldn't hurt to try from Kubrick dropped to a CLI shell, see if you can get any further.

[knc1]

Originally Posted by KingD

Hi knc1,

Thank you for the reply. The device was put in airplane mode for quite some time and at the time it was not in a place with Wi-fi connection. Will it still perform OTA update?

The battery was low but from the system battery icon it could still work for hours.

If the OTA update had been downloaded at any time prior - yes.

The battery icon shows terminal voltage - not remaining storage capacity.

@NiLuJe: Last I checked (admittedly, many firmware revisions ago) the updater also **only** checks the battery terminal voltage.

Note: Battery terminal voltage on a Li-Ion battery **does not** indicate storage (or remaining storage) capacity.

The Kindle **can** check the battery storage capacity, and the various battery report add-ins we have here does report it.
A tad bit too late in this case.

This is a Paperwhite - but it has fallen back to downloader mode -
so the utilities on the KUBRICK cd may be able to deal with the problem.

Hint (too late here):
I make it a habit to put my Kindles on external power **before** turning them on after a period of non-use.

[NiLuJe]

@knc1: Good point, I don't quite remember the details, but I *think* it's doing it the right way, to end up checking a % level of charge.

If anyone wants to fire IDA to confirm, enjoy ;p.

[KingD]

Bad news. I tried Kubrick in VM first. It stuck on waiting for device to enter fastboot mode.

Kubrick on physical machine doesn't work for me either. Although it boots, I get "missing java files" after that and my keyboard does not seem to be recognized.

BTW, the device is Wi-Fi only and has been put in airplane mode for quite some time (more than a month I guess, only turned on for downloading).. so maybe I have to check battery status more frequently..

[knc1]

Originally Posted by KingD

- - - -
Kubrick on physical machine doesn't work for me either. Although it boots, I get "missing java files" after that and my keyboard does not seem to be recognized.
- - - -

Most likely cause: Your PC is too new
(kernel is having problems with hardware that is newer than it is configured for).

Try an older machine.

[KingD]

Just now I managed to call Kubrick from Debian live CD. But it even can't pass download mode check ...