HP Deskjet 3820 Color Inkjet Printer - Manual (Page 66)

there may be a problem with a print cartridge
●
Verify that the correct print cartridges are installed.
●
Check if a print cartridge is low on ink or improperly installed.
See also:
print cartridges
checking the print cartridge status
resume light is flashing
the printer may be out of paper
1. Place paper in the In tray.
2. Press the Resume button on the front of the printer.
there may be a paper jam
Follow these instructions to clear a paper jam .
the printer may be ready to print the second side of a two-sided document
Follow the onscreen instructions for printing the second side.
These instructions appear when you manually print a two-sided document.
power light is flashing
the printer is preparing to print
The light stops flashing when the printer has received all data.
all lights are flashing
the printer may need to be restarted
1. Press the Power button to turn off the printer, then press the Power button to
turn the printer on.
Proceed to step 2 if the lights continue to flash.