IBM FAStT500 User Guide - Page 62

• If the amber fan light is on or the green power indicator remains off, make sure that the controller fan is seated securely in the slot and that the lever is snapped into place. • If the controller fan indicator remains on, it might indicate a problem with the new controller fan. Replace the controller fan with a spare, if available. If not, turn off the controller unit to prevent it from overheating until you can replace the fan. 6 Replace the controller unit bezel, as shown in Figure 7 on page 11. Fan and communications module The fan and communications module is a single, removable unit containing two cooling fans, two serial ports, and two Ethernet ports. This module plugs into a slot at the center back of the controller unit, just above the power supplies (see Figure 25 on page 44). It has a locking lever and a pull handle for securing and removing the fan and communications module. The module contains dual fans that provide a redundant cooling system to both power supplies. If one fan within the module fails, the other continues to operate. A single fan provides sufficient air circulation to prevent the power supplies from overheating until you can replace the entire fan and communications module. Servicing notes Consider the following when servicing the fan and communications module: • The fan and communications module contains two serial RS-232 connections used for diagnostic purposes and two Ethernet RJ-45 connections used for direct networkmanagement. • You can hot swap the fan and communications module as long as you complete the exchange within 15 minutes from when you remove the failed unit until you install the new one. • It is unlikely that both fans in the fan and communications module will fail simultaneously. Such a failure will cause one or both power supplies to overheat. In these circumstances, the amber power supply indicator light on the bezel turns on and the overheated power supply automatically shuts down (the green power indicator light turns off). Once the ambient air temperature cools below 70ºC (158°F), the power supply automatically turns on. Replace the failed fan and communications module then check the power supply indicator lights (fault indicator light on the front and power indicator light on the back). If the power supply fault indicator light remains on, replace the power supply. For more information about indicator lights, see "Checking the indicator lights" on page 15. • If you replace the fan and communications module and still experience problems, the controller unit might have defective components or connections. Check the storagemanagement software for indications of other component failures. 42 IBM FAStT500 RAID Controller Enclosure Unit User's Guide