Cooling fans are used to solve the thermal problems of most critical electronic parts in systems. Therefore, it is very important to monitor the fans condition periodically dealing with the detection, location and analysis of the possible faults. The fault diagnosis of rotating systems is increasingly paying attention. The main purpose of this study is to investigate the possible faults in a rotating system using vibration and noise measurements. A simple cooling fan is used for implementing the experimental measurement. Some artificial faults are performed for measuring the system responses. The empirical results show that Acoustic Emission (AE) technique is very useful to detect the faults at the system.