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HP ElitePad 900 Troubleshooting
No matter what you do, you can't get the tablet to turn on.
If the tablet won't turn on, especially if it has not been used recently or has been used extensively without charging, you may simply have a drained battery. Plug the tablet into the AC adapter and see if anything happens. If the tablet still will not turn on after five minutes of charging, you may have a damaged AC adapter or a bad battery.
If the tablet will not charge, the probable cause is a bad AC adapter. This may be caused by prolonged use, or other physical damage. Check all wires for the adapter for any damage. If there is no damage, try either a different wall socket for the AC adapter, or plugging in a different adapter for the tablet. If the tablet still does not charge , the battery may need to be replaced.
The speakers are not working at all, or are only emitting low volume sounds.
Check the volume settings on the tablet. Mute may have been turned on, or the volume setting could be set lower. Simply turn mute off or raise the volume level. Also check the audio output settings. The audio may be playing out of the headphones instead of the speakers.
If the volume is on, and the audio is trying to play thought the speakers, they may need to be replaced.
There is no display on the screen of the tablet.
Make sure the tablet is turning on. If the tablet will not even turn on, look at the troubleshooting guide for "Tablet Won't Turn On".
Check brightness settings, the display may be on a low brightness and needs to be turned up.
The display may be damaged or have loose cables. Refer to this guide to replace the screen or to check the cables.