Possible causes include a broken optical fiber, disconnected jumper, wrong port connection, dirty connector, excessive bending, incorrect channel selection, or device startup failure. Fiber optic temperature sensors are used in a variety of harsh environment applications. It helps detect overheating, fire risks, cable faults, leakage, and abnormal temperature changes early. Common problems often come. commercial gas turbines to measure the temperature at various regions of interest within the turbine system. This work will focus on failure mechan sms observed at. VIAVI OTDRs allow technicians all over the world to characterize optical cables by measuring the optical length, the global loss and, the common events such as splices, connectors and slopes that affect cable performance and signal transmission. Now the Brillouin OTDR (B-OTDR) capability, within. These features of optical fibers make them a useful tool for various sensing applications including in medicine, automotives, biotechnology, food quality control, aerospace, physical and chemical monitoring. Among all the reported applications, optical waveguides have been widely exploited to. Fiber-optic high-temperature sensors are gradually replacing traditional electronic sensors due to their small size, resistance to electromagnetic interference, remote detection, multiplexing, and distributed measurement advantages.