Kindle Keyboard 3G – power slider stops working randomly, USB stops enumerating;

[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.

[dmitryshura]

Additional observation:
If I connect external power (USB charger) and reboot the Kindle while it stays connected to power, the problem does not appear.
It starts happening again only after I unplug the power cable.

[Tarana]

Failure of the power slider was what killed two of my 5 kindle 3's so far. I think you may have the same problem and it is the spring attached to the power slider. I was unable to find an appropriate new replacement spring. One guy bought my unusable kindle from me ($5) and replaced the spring with the spring from his screen damaged kindle 3 and that worked.

[dmitryshura]

Originally Posted by Tarana

Failure of the power slider was what killed two of my 5 kindle 3's so far. I think you may have the same problem and it is the spring attached to the power slider. I was unable to find an appropriate new replacement spring. One guy bought my unusable kindle from me ($5) and replaced the spring with the spring from his screen damaged kindle 3 and that worked.

Thanks for the suggestion!

I’m aware of the common K3 power slider/spring failure, but my symptoms don’t fully match a purely mechanical issue.

Key observation:
If I connect external power (USB charger) and reboot the Kindle while it stays connected to power, everything works normally and the issue does not appear.
The problem starts again only after I unplug the power cable.

If it was only the slider spring/mechanics, I would expect the behavior to be identical regardless of whether a charger is connected.

So at the moment I suspect something related to power management / battery mode vs external power mode (or a battery/PMIC-related state), rather than the slider mechanism itself.

Did you ever notice your slider/spring failures behaving differently on charger vs on battery?

[gbm]

You have a bad slider or a bad battery. You should think about replacement, or take a chance on buying a parts reader.

Rule of thumb if the cost to repair is equal to half the cost or greater than the cost of new, then buy new.

bernie

Originally Posted by dmitryshura

Thanks for the suggestion!

I’m aware of the common K3 power slider/spring failure, but my symptoms don’t fully match a purely mechanical issue.

Key observation:
If I connect external power (USB charger) and reboot the Kindle while it stays connected to power, everything works normally and the issue does not appear.
The problem starts again only after I unplug the power cable.

If it was only the slider spring/mechanics, I would expect the behavior to be identical regardless of whether a charger is connected.

So at the moment I suspect something related to power management / battery mode vs external power mode (or a battery/PMIC-related state), rather than the slider mechanism itself.

Did you ever notice your slider/spring failures behaving differently on charger vs on battery?

[dmitryshura]

Originally Posted by gbm

You have a bad slider or a bad battery. You should think about replacement, or take a chance on buying a parts reader.

Rule of thumb if the cost to repair is equal to half the cost or greater than the cost of new, then buy new.

bernie

Thanks, Bernie.

I actually have a second K3 as a parts unit (broken screen. model without wlan), so I can swap hardware to localize.

I agree battery/PMIC behavior sounds more plausible. I’ll start with a battery replacement first.

If that doesn’t change anything, I’ll swap the entire slider assembly from the donor unit just to rule it out completely.

[dmitryshura]

Originally Posted by dmitryshura

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).

UPD (Amazon registration / OTP issue solved):

Turned out it was not a Kindle problem. Registration was failing because of my home network DNS/security filtering.
I had “secure DNS” / DNS filtering enabled in my network, and for some reason it was breaking Amazon authentication for the Kindle.

Fix:
I created a separate Wi-Fi network routed through a VPN to my datacenter (clean DNS / no filtering) — after that the OTP started being accepted and the Kindle registered successfully.

What worked for me step-by-step:

1. Enter email + password on the Kindle.
2. It shows a login error.
3. Then an OTP arrives to my email.
4. Without entering anything on the Kindle, reboot the device.
5. Try to register again, but enter the OTP instead of the password.
6. Kindle registered.

So if anyone is stuck with “OTP not accepted” on an old Kindle, check your DNS/adblocking/secure DNS filtering.

[Frogm4n]

I'm not clear from your initial post: Does the Kindle continue to otherwise operate normally in the "glitch state" where the slider does not seem to work?

[dmitryshura]

Originally Posted by Frogm4n

I'm not clear from your initial post: Does the Kindle continue to otherwise operate normally in the "glitch state" where the slider does not seem to work?

Yes, in the "glitch state" it can still appear to work normally for reading: the screen updates, page turns and menus are responsive, and I can keep reading.

However, in that state:

• a short slide of the power switch does nothing (no LED / no sleep-wake),
• USB also stops enumerating (PC doesn’t detect it at all),
• and if it goes to sleep by timeout/screensaver, it often cannot be woken with the slider.

So it’s not a full freeze/crash, more like certain functions (sleep/wake event handling and USB) stop responding until a reboot.

[Tarana]

Originally Posted by dmitryshura

Did you ever notice your slider/spring failures behaving differently on charger vs on battery?

Not really. Did the same thing whether on charger or not. It fully charged so I knew it wasn't battery.

[dmitryshura]

Originally Posted by Tarana

Not really. Did the same thing whether on charger or not. It fully charged so I knew it wasn't battery.

Thanks for clarifying!

In my case there’s a pretty consistent difference between on charger vs on battery:

If I reboot the Kindle while connected to external power and keep it plugged in, it can run without the slider/USB glitch. This whole week I’ve been using it basically "as a desk Kindle" kept on the charger and I haven’t been able to trigger the problem as long as the cable stays connected.

As soon as I unplug the charger, the glitch eventually returns (sometimes within minutes).

I’ve already ordered a replacement (aftermarket) battery and will report back once it arrives, since the original battery in my donor K3 had swollen and was disposed of.