290 Troubleshooting Your SystemTroubleshooting USB DevicesNOTE: USB devices can be connected only to the blade front panel. Total length ofa USB cable should not exceed 3 m (9.8 ft).1 Ensure that the blade(s) is turned on.2 Check the USB device connection to the blade.3 Swap the USB device with a known-working USB device.4 Connect the USB devices to the blade using a powered USB hub.5 If another blade is installed, connect the USB device to that blade. If theUSB device works with a different blade, the first blade may be faulty. See"Getting Help" on page 337.Responding to a Systems Management AlertMessageThe CMC management applications monitor critical system voltages andtemperatures, and the cooling fans in the system. For information about theCMC alert messages, see the Configuration Guide.Troubleshooting a Wet EnclosureCAUTION: Many repairs may only be done by a certified service technician. Youshould only perform troubleshooting and simple repairs as authorized in yourproduct documentation, or as directed by the online or telephone service andsupport team. Damage due to servicing that is not authorized by Dell is not coveredby your warranty. Read and follow the safety instructions that came with theproduct.1 Turn off the system.2 Disconnect the power supplies from the PDU.CAUTION: Wait until all of the indicators on the power supplies turn off beforepreceding.3 Remove all of the blades. See "Removing a Blade" on page 145.4 Remove the power supply modules. See "Removing a Power SupplyModule" on page 266.5 Remove the fan modules. See "Removing a Fan Module" on page 269.
