IBM Aptiva Series, Обслуживание оборудования

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General Information 1-3
be failing are listed in order of the most probable failure and. Also, the FRU
parts are defined as a replaced unit which are not repaired in the field.
Measuring Voltages: Many check procedure steps instruct you to measure
voltages on cable plugs and electronic board connectors. If you are asked to
measure voltage at several places on a plug or connector, a chart next to or
near the instruction indicates the number of the plug or connector, the pin
numbers you should measure, the signal name, and the correct voltage for the
condition you are measuring. Measure the voltage only at the pins listed in the
chart. Remember to set the meter on the correct scale and to put the meter
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 Aids
This chapter contains information outside the check procedures to help you
diagnose a failure of a specific part. Some diagnostic aids are resident in the
machine, such as the Power-On Self Test (POST). The machine performs the
POST each time it is powered on. Use this information throughout the
diagnostic procedures. You should become familiar with the POST and be
able to determine if the machine performed all the steps.
POST: The normal POST is initiated automatically each time the system unit
is powered on. The POST is a series of system checks and initializations that
verify the correct operation of the base system.
After a successful POST, a single short beep is generated. The system
attempts to load an operating system. The system can be customized for
different startup (boot) methods by BIOS Setup Utility.
The system's default startup sequence automatically looks for the operating
system files on the hard disk if the files are not found on diskette.
Note: Remember that the POST does not test all areas, but only those that
allow the system to operate well enough to run the Diagnostics
program.
Repair Information
This chapter contains removal and replacement instructions.