[dmitryshura]

Kindle Keyboard 3G (K3) – power slider stops working randomly, USB stops enumerating; only 20–30s hard reset works

Hello everyone.

Device: Kindle Keyboard 3G (K3)
Firmware: 3.4.3 (latest for K3)
Issue started suddenly, no drops or physical damage. I don’t use the device often.

Symptoms
Most of the time the Kindle works perfectly (reading is fine, UI is responsive), but after some minutes it enters a “glitch state”:

1. Sleep/Wake via power slider stops working.
   • Short slide does nothing: no LED, no reaction, cannot put it to sleep or wake it.
   • When this happens, the slider “feels” mechanically normal, but the device ignores it.
2. Hard reset still works, but with a delay.
   • If I hold the slider for ~20–30 seconds, it eventually reboots.
   • There is a strange delay: I can release the slider, wait a few seconds, then the green LED turns on for ~10 seconds, then the reboot starts.
   • Earlier (before the problem) the reboot felt much more immediate.
3. USB stops working at the same time.
   • When the glitch state happens, connecting to PC does nothing (no Windows “device connected” sound, Kindle doesn’t enumerate).
   • USB works normally until the glitch state begins.
4. If the Kindle goes to sleep by itself (screensaver), it may not wake up.
   • Sliding the power switch does nothing (no LED).
   • The only way to “wake” it is again the long 20–30s hard reset.
5. After reboot, the slider may work again… but only for a short time (1–5 minutes).
   • During that window it works flawlessly (I can sleep/wake many times quickly, both on Home screen and while reading).
   • Then suddenly it stops again.

There is no clear trigger (book/app/menu doesn’t matter). It can happen anywhere and is “fixed” only temporarily by rebooting (sometimes I need 2 reboots).

What I already tried (no change)

• Updated to 3.4.3 (already on it).
• Hard reset / factory reset.
• Drained the battery completely and charged again.
• Tested on external power vs battery: same behavior.
• Tested right after reset, with no books / minimal content: same behavior.
• Removed jailbreak / factory reset / reinstalled jailbreak & hacks: same behavior at every stage.
• Also tried disabling/enabling radios; removing SIM: no change.

(I even tested with the 3G/Wi-Fi hardware disconnected internally — still happens.)

Amazon registration problem (after reset)
After factory reset I can’t register the Kindle back to my Amazon account:

• Amazon sends a one-time code valid for ~10 minutes, but the Kindle rejects it.
• Entering password+code combined also does not work (I know this workaround exists for some old Kindles, but not in my case).

I will contact Amazon support separately, but I mention it in case it’s related.

My current hypothesis (software)
It looks like a software component that handles the sleep/wake slider event sometimes hangs or crashes. When it’s “dead”, the Kindle ignores short slider events and USB also stops responding, but the long 20–30s hold still reboots, which might be a lower-level hard reset path (kernel/PMIC/watchdog) independent of the normal UI event handling.

At the same time, the Kindle can still enter sleep/screensaver by timeout, so either:

• sleep-by-timeout is handled differently than wake-by-slider, or
• the power management is only partially stuck.

Questions

1. Has anyone seen this pattern on K3?
2. Which logs should I check on K3 to confirm what is hanging (power management / framework / USB)?
3. Any known fixes besides replacing hardware? (I already tested factory reset + minimal content + no radios, same result.)

Thanks in advance.