IBM xSeries 342 2RX Maintenance Manual

Contents

DiagnosticsThis section provides basic troubleshooting information to help you resolve somecommon problems that might occur with your server.Diagnostic tools overviewThe following tools are available to help you identify and resolve hardware-relatedproblems:v POST beep codes, error messages, and error logsThe power-on self-test (POST) generates beep codes and messages to indicatesuccessful test completion or the detection of a problem. See “POST” on page 12for more information.v Diagnostic programs and error messagesThe server diagnostic programs are stored in upgradable read-only memory(ROM) on the system board. These programs are the primary method of testingthe major components of your server. See “Diagnostic programs and errormessages” on page 13 for more information.v Light path diagnosticsYour server has light-emitting diodes (LEDs) to help you identify problems withserver components. These LEDs are part of the light-path diagnostics that arebuilt into your server. By following the path of lights, you can quickly identify thetype of system error that occurred. See “Light path diagnostics” for moreinformation.Identifying problems using LEDsYour server has LEDs to help you identify problems with some server components.These LEDs are part of the light path diagnostics built into the server. By followingthe path of lights, you can identify the type of system error that occurred. See thefollowing sections for more information.Power supply LEDsThe AC and DC Power LEDs on the power supply provide status informationabout the power supply. See “Power supply LED errors” on page 90.Light path diagnosticsYou can use the light path diagnostics built into your server to quickly identify thetype of system error that occurred. The diagnostics panel is under the ″windtunnel.″ Your server is designed so that any LEDs that are illuminated remainilluminated when the server shuts down as long as the AC power source is goodand the power supplies can supply +5V DC current to the server. This featurehelps you isolate the problem if an error causes the server to shut down. See“Light path diagnostics table” on page 12.Diagnostics panelThe following illustration shows the LEDs on the diagnostics panel on the systemboard. See “Light path diagnostics table” on page 12 for information on identifying© Copyright IBM Corp. 2000, 2001 11