26IntroductionThis chapter contains the check procedures used to diagnose the causes ofproduct failures. The diagnostic information consists of:Start: This is the starting point for any diagnostic action. Based on high-levelsymptoms, the check procedure directs you to more detailed procedures tohelp resolve machine failures.Index of Symptoms, Messages, Error Codes, or Beeps: The tables forBIOS Error Messages, Codes, Beeps, and Error Symptoms list symptomsalong with their probable causes, and direct you to the applicable checkprocedures to help resolve machine failures. These tables also list the fieldreplaceable units (FRUs) most likely to cause a particular problem.Check Procedures: When the Start check procedure or the Index ofSymptoms, Messages, Error Codes, or Beeps tables point you to a specificcheck procedure, proceed to that section. If there are any notes or instructionsat the top of the page, read them before you begin with the procedure.Carefully read each step of the check procedure and perform the steps asinstructed. If you do not remember the location of a specific part or test point,or an adjustment or removal procedure, see the chapter that contains thatinformation. Always return to the check procedure after you do this. In somecases, you are referred to other check procedures to detect the cause of thefailure.
