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Hardware Diagnostic Testing
This section provides a more detailed approach to identifying a hardware problem and locating its source.
Caution: Turn off devices before disconnecting cables: Before disconnecting any peripheral cables from the system, turn off the system and any external peripheral devices. Failure to do so can cause permanent damage to the system and/or the peripheral devices.
1Turn off the system and all external peripheral devices. Disconnect each device from the system, except for the keyboard and the video monitor.
2Make sure the system power cord is plugged into a properly grounded AC outlet.
3Make sure your video display monitor and keyboard are correctly connected to the system. Turn on the video monitor. Set its brightness and contrast controls to at least two thirds of their maximum ranges (see the documentation supplied with your video display monitor).
4If the operating system normally loads from the hard disk drive, make sure there is no diskette in drive A and no
5If the power LED does light, attempt to boot from a floppy diskette or from a
6Turn on the system. If the power LED does not light, see “Power Light Does Not Light.”
Verifying Proper Operation of Key System Lights
As POST determines the system configuration, it tests for the presence of each mass storage device installed in the system. As each device is checked, its activity light should turn on briefly. Check for the following:
•Does the diskette drive activity light turn on briefly? If not, see “Diskette Drive Activity Light Does Not Light.”Diskette Drive Activity Light Does Not Light
•If system LEDs are illuminated, see LED Information“” for a description of
