336 Chapter 25 Replacing or installing a cooling fanN0060612N0060612Installing an expansion unit fanTo install an expansion unit fan1 Place the fan in the expansion unit so that the label faces the back wall of the unit.2 Align the screw holes in the fan with the screw holes in the expansion unit and attach the fan.3 Connect the fan power supply cable to the hub board.4 Replace the cover.5 Restore the BCM system to operation. For details, refer to “Restarting the system aftermaintenance” on page 234.The BCM system starts up when you connect the AC power cord. The start-up process takesseveral minutes to complete.6 Test the direction of the fan exhaust air flow to determine if the fan is correctly installed.a Hold a piece of paper or your hand close to the fan exhaust. A correctly installed fan blowsair away from the main unit.b If the fan exhaust air flow is incorrect, remove the cooling fan (see “Removing a BCM200cooling fan” on page 331) and reinstall the fan in the correct orientation (this procedure).Troubleshooting cooling fansThere are three LEDs on the front of the BCM base function tray and one on the front of theexpansion unit used to assess fan functionality. Table 84 describes the possible states of the fanand temperature LEDs.Warning: Protect the hardware components against damage from electrostatic discharge.Always wear a grounded wrist strap before you handle components. Always place thecomponents in a static-free container.Note: Ensure the label of the new fan faces the back wall of the BCM expansion unitchassis. Airflow is out of the chassis as indicated by the arrows imprinted on the fan.Table 84 Fan and temperature LEDs on the base function trayLED Label Description Green LED On Red LED On (Only)Temperature Temperature is belowthreshold.Temperature is in alarm status.Possible fans failure.Fans All installed fans are working. There is a problem with a minimum ofone fan.Power All components are working. Component failure.
