Amazon Kindle Kindle Keyboard 3G User Manual page 105

Kindle User's Guide 105
Appendix A Troubleshooting
If your Kindle is unresponsive, then try resetting it by doing the following:
1. Disconnect your Kindle from any power source.
2. Slide and hold the power switch for 15 seconds before releasing.
Note that the screen will be blank for approximately 30 seconds while your Kindle restarts.