Universal Serial Bus (USB) port problemsv Follow the suggested actions in the order in which they are listed in the Action column until the problem issolved.v See Chapter 5, “Parts listing, System x3750 M4 Types 8722 and 8733,” on page 195 to determine whichcomponents are customer replaceable units (CRU) and which components are field replaceable units (FRU).v If an action step is preceded by “(Trained service technician only),” that step must be performed only by aTrained service technician.Symptom ActionA USB device does not work. 1. Make sure that the correct drivers are installed on the server. See theproduction documentation for the USB device or the manufacturer’s websitefor information about the device drivers.2. Use the Setup utility to make sure that the device is configured correctly (see“Using the Setup utility” on page 127).3. If the USB device is connected into the hub or the console breakout cable,unplug the device and connect it into the USB port on the front of the server.4. Run the DSA USB diagnostic test (see “Running the DSA Preboot diagnosticprograms” on page 171).Video problemsSee “Monitor and video problems” on page 181.Solving power problemsPower problems can be difficult to solve. For example, a short circuit can existanywhere on any of the power distribution buses. Usually, a short circuit willcause the power subsystem to shut down because of an overcurrent condition. Todiagnose a power problem, use the following general procedure:1. Check the IMM event log and resolve any errors related to the power (see“Power problems” on page 184).2. Check for short circuits, for example, if a loose screw is causing a short circuiton a circuit board.3. Remove the adapters and disconnect the cables and power cords to all internaland external devices until the server is at the minimum configuration that isrequired for the server to start (see “Solving undetermined problems” on page189 for the minimum configuration).4. Reconnect all ac power cords and turn on the server. If the server startssuccessfully, reseat the adapters and devices one at a time until the problem isisolated.If the server does not start from the minimum configuration, see “Power-supplyLEDs” on page 164 to replace the components in the minimum configuration oneat a time until the problem is isolated.Chapter 4. Troubleshooting 187
