The optical module is faulty or not securely installed. If the transmit optical power is abnormal, replace the. An optical module is a critical component in modern optical communication systems, directly affecting transmission stability, network reliability, and operational efficiency. However, during installation and daily operation, various issues may arise. Yet in real-world deployments, many data centers, ISPs, and enterprise networks still experience unexpected link failures after installation. But when a link suddenly goes. However, even in well-designed infrastructures, engineers frequently encounter issues such as SFP modules not being detected, no link light after installation, or unstable fiber connections.