Intermittent problemsUse this information to solve intermittent problems.v Follow the suggested actions in the order in which they are listed in the Action column until the problem issolved.v If an action step is preceded by “(Trained technician only),” that step must be performed only by a trainedtechnician.v Go to the IBM support website at http://www.ibm.com/supportportal/ to check for technical information, hints,tips, and new device drivers or to submit a request for information.Symptom ActionA problem occurs onlyoccasionally and is difficult todiagnose.1. Make sure that:v All cables and cords are connected securely to the rear of the server andattached devices.v When the server is turned on, air is flowing from the fan grille. If there is noairflow, the fan is not working. This can cause the server to overheat andshut down.2. Check the system-error log or IMM event logs (see “Event logs” on page 146).The server resets (restarts)occasionally. 1. If the reset occurs during POST and the POST watchdog timer is enabled (clickSystem Settings > Recovery > System Recovery > POST Watchdog Timer inthe Setup utility to see the POST watchdog setting), make sure that sufficienttime is allowed in the watchdog timeout value (POST Watchdog Timer). If theserver continues to reset during POST, see Appendix B, “UEFI/POSTdiagnostic codes,” on page 665 and DSA messages.2. If neither condition applies, check the system-error log or IMM system-eventlog (see “Event logs” on page 146).Keyboard, mouse, or USB-device problemsUse this information to solve keyboard, mouse, or USB-device problems.v Follow the suggested actions in the order in which they are listed in the Action column until the problem issolved.v If an action step is preceded by “(Trained technician only),” that step must be performed only by a trainedtechnician.v Go to the IBM support website at http://www.ibm.com/supportportal/ to check for technical information, hints,tips, and new device drivers or to submit a request for information.Symptom ActionAll or some keys on thekeyboard do not work. 1. Make sure that:v The keyboard cable is securely connected.v The server and the monitor are turned on.2. If you are using a USB keyboard, run the Setup utility and enable theoperation.3. If you are using a USB keyboard and it is connected to a USB hub, disconnectthe keyboard from the hub and connect it directly to the server.4. Replace the keyboard.158 IBM System x3550 M4 Type 7914: Installation and Service Guide
