bd flow cytometer liquid line system is not open

Is the questioner asking "What is the reason that the bd flow cytometer liquid line system is not on"? The environment is not clean enough. If the environment is not clean enough for the bd flow cytometer liquid line system to turn on, you need to clean the dust on the connecting wires. If the environment is not clean enough, reinstall the BD PAC board in the computer (under the guidance of a BD engineer).