Hello Gilad,
Please try connecting the printer to a different power socket, without using any power stips, surge protectors, etc.
If the same behaior appears you will need to service the printer as it seems as an hardware failure.
You may find the contact details to contact HP support and service the device by selecting your location and following Technical support after you buy in the following link:
http://www8.hp.com/us/en/contact-hp/ww-contact-us.html
Shlomi
