The printer is preparing to print if the Power indicator is flashing. When the HP printer light blinking won't print has received all data, the indicator stops flashing. An open cartridge door is indicated by a rapidly blinking light. Fast flickering power lights indicate that the printer is malfunctioning. The flashing resume light indicates that there is a paper jam or that the paper tray is empty.Also check the status of your printer cartridge and try replacing it with a new one if it is not good enough.