Disconnect the unit completely from the AC outlet for 5 or 10 minutes, then plug it back again.It will works.
Also I suspect it may be a loose power switch, or a problem with the power supply.
If it is a USB printer that derives power through the USB cable and not from a seperate power cable, then check the USB cable. That may be the source of the problem if the cable is bad.
Try the following solutions in the order presented to resolve the issue...
Solution one: Press and quickly release the Power button
Press and quickly release the Power button ( ) to start a Power On/Off cycle. Do not hold down the button .
Press and quickly release the Power button
If you press and hold the Power button too long, the product might turn on and then off without restarting. If this happens, press and quickly release the Power button ( ) again.
If these steps resolved the issue , you do not need to continue troubleshooting.
If the issue persists , continue to the next solution.
Solution two: Check the electrical connections and outlet
Unplug the power cord from the electrical outlet, or the power strip or surge suppressor.
NOTE: The power cord detaches from the power module. The term power supply refers to both the power module and the power cord.
Carefully inspect the power cord for visible damage.
If the power cord or power module shows any damage, contact HP to replace the power supply.
Disconnect the power supply from the back of the product.
Wait at least 30 seconds, and then plug the disconnected power supply into an electrical outlet. Do not use a power strip or surge suppressor.
If the green light (LED) on the power supply does not light up, contact HP to replace the power supply.
Reconnect the power module to the product.
Press and quickly release the Power button ( ) to turn the product on.
If the product still does not turn on, connect the product to an electrical outlet in another room, and then quickly press and release the Power button ( ) to turn on the product.
If the product turns on , the electrical outlet in the original room caused the issue.
If the product still does not turn on , continue with the next solution.
Solution three: Check the USB cable
Disconnect the USB cable from the back of the product.
( chek the figure)
Press the Power button ( ) to turn on the product.
If the product turns on with the USB cable disconnected , replace the USB cable.
If the product still does not turn on , continue to the next solution.
Solution four: Check the battery
If your HP product has a battery, follow these steps:
Check the battery light. If the light is red, recharge the battery.
If the battery light is still red after recharge, replace the battery.
( chek the figure)
1 - Slide the battery release slider in the direction of the arrow
2 - Remove the battery
Instructions for recharging and replacing a battery are available on the HP Web site.
Solution five: Replace the power supply
If you have completed all of the troubleshooting steps and are still experiencing a problem, contact HP to replace the power supply for your product.
Solution six: Service the printer
If you have completed all the steps listed above and are still experiencing a problem, service the product.
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