IBM Aptiva 2140 Hardware Maintenance Service

Also see for Aptiva 2140: Maintenance service manual Hardware maintenance service

Using the Check ProceduresFailing Parts or Assemblies: The check procedures generally help youtrace a problem to one part or assembly. The last step of the specific checkprocedure you are using indicates that a part or assembly is failing. Youshould inspect the part or assembly before you decide to replace it. It mightbe loose, dirty, or in need of a small repair. The check procedures mightlead you to two, or even three, possible failing parts or assemblies. Theparts that might be failing are listed in order of the most probable failure.Measuring Voltages: Many check procedure steps instruct you to measurevoltages on cable plugs and electronic board connectors. If you are askedto measure voltage at several places on a plug or connector, a chart next toor near the instruction indicates the number of the plug or connector, the pinnumbers you should measure, the signal name, and the correct voltage forthe condition you are measuring. Measure the voltage only at the pins listedin the chart. Remember to set the meter on the correct scale and to put themeter leads in the correct position for the voltage you are asked to measure.Note: Use frame ground for the ground reference. Attach the black meter(ground) lead to frame ground, except where specified otherwise.Diagnostic AidsThis chapter contains information outside the check procedures to help youdiagnose a failure of a specific part. Some diagnostic aids are resident inthe machine, such as the Power-On Self Test (POST). The machineperforms the POST each time it is powered on. Use this informationthroughout the diagnostic procedures. You should become familiar with thePOST and be able to determine if the machine performed all the steps.POST: The normal POST is initiated automatically each time the systemunit is powered on (when Power Management is enabled, a shorter versionof POST is initiated—see “Power Management” on page 1-21). The POSTis a series of system checks and initializations that verify the correctoperation of the base system. Two classifications of malfunctions might bedetected during the POST: critical and noncritical.Critical malfunctions prevent the system from operating at all, or could causeincorrect results that are apparent to the user. Examples of critical errorsinclude processor or interrupt controller malfunctions. If a critical error isdetected during the POST, an attempt is made to indicate the error, and alltesting halts.General Information 1-3Get user manuals: See SafeManuals.com