Dirty, poorly aligned, or damaged connectors are a common cause of problems in fiber optic systems. These issues can lead to high insertion loss or a complete loss of the signal. Or it could be caused by the quality of the connector itself, such as poor end-face geometry that doesn't pass the. Fiber optic troubleshooting is an essential skill for network administrators, technicians, and engineers responsible for maintaining and repairing fiber optic systems. Maintenance personnel can refer to this document for step-by-step troubleshooting when dealing with faults arising from the following. A well-built fiber link rarely fails, but when it does the symptoms can be short, confusing, and expensive to chase. This guide lists the actual, field-proven problems technicians encounter most often and gives step-by-step troubleshooting actions you can copy into your maintenance routine. Keep. Fiber optic cables are the backbone of modern communications, delivering high-speed data over long distances with minimal loss. However, in real-world installations, whether underground, aerial, or in harsh industrial environments, fiber cables can and do fail.