Reason:Negative pressure overrate.
Settlement:Adjust the negative pressure to the normal range of -3.8 or so（Vary in different areas）.
Reason:Ink supply timeout.
Settlement:Settlement: Check the ink tank, if the ink is empty, fill it, otherwise there may be ink pump damage or leak .
Reason:Communication failure between external device control board and head board.
Settlement:Check the communication cable or replace the head board or external device control board.
Reason:The ink flows into the negative pressure box.
Settlement:Check if the negative pressure too high or the liquid sensor malfunctioned, clean or replace the air pipe, replace the ink pressure valve if infiltrated.
Reason:Ink tank staving.
Settlement:Locate the color and refill.
Reason:Filter cotton too dirty or the voltage is unstable or the lamp lifetime is over.
Settlement:Replace the filter cotton or check the power supply or change the lamp.
Reason:High temperature expansion jam.
Settlement:Check the causing of jamming and make mechanical modification.
Reason:Large current operation.
Settlement:Replace the rocker switch, ensure the connections are solid when replacing.
Q:￠4X2.4 Ink tube The negative pressure decrease and fluctuate when carriage running or the ink tu
Reason:Crushed by the high-speed running of the chain.
Settlement:Replace the ink tube.
Reason:Computer case ungrounded, hot plugging communication cable or frequent shutdown.
Settlement:Replace the external device control board, make sure the machine and computer is off when operating the communication cable, at least 30 seconds between each on/off, solid grounding of the computer case is necessary.
Reason:Origin switch is stained with ink, the light is blocked.
Settlement:Wipe clean with alcohol or replace.
Settlement:Anti-Virus, or record parameters of color registration, temperature and voltage, then reinstall the computer and software.
Settlement:Adjust the tightness of the fixed screw.
Reason:Black ink print head surface is easy to be cured.
Settlement:Use clean cloth with cleaner to clean the nozzle surface repeatedly until it's normal again.
Reason:The dust in negative pressure control valve affected the air flow.
Settlement:Clean the negative pressure control valve every month.
Reason:The data transfer card is not plugged in or the driver is not installed correctly or the gold finger is dirty.
Settlement:Reinsert data transfer card or reinstall the driver or clean the gold finger.