✅ Use the ICIRE checklist on every job: I nspect → C lean → I nspect again → R oute (min bend radius) → E ndface protect. Following this 5-step process eliminates 90%+ of installation-related fiber failures. This guide offers practical steps to troubleshoot fiber optic cable issues, covering common problems, key tools, and preventive measures to ensure stable performance. The most common problems usually fall into four categories: Physical Layer: Transmission Performance: Equipment and Module Failures:. When issues like signal loss, slow speeds, or intermittent connectivity arise, systematic troubleshooting is key. Fiber optic networks have become the backbone of modern communication, but anyone who has.