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Confirming Loading of the Operating System
Once the system boots up, the operating system prompt appears on the screen. The prompt varies according to the operating system. If the operating system prompt does not appear, refer to Problems With Application Software found later in this chapter.
Specific Problems and Corrective Actions
This section provides possible solutions for the following specific problems:
power LED does not light
system cooling fans do not rotate
no characters appear on screen
characters on the screen appear distorted or incorrect
floppy disk drive access LED does not light
hard disk drive access LED does not light
TRCU does not boot
problems with application software.
Try the solutions in the order given. If you cannot correct the problem, contact your service representative for assistance.
Power LED Does Not Light
Check the following.
Is the system operating normally? If so, the power LED is probably
Tdefective.
Are there other problems with the system? If so, check the items listed under System Cooling Fans Do Not Rotate.
System Cooling Fans Do Not Rotate
Note: In addition to the cooling fans that are an integral part of each power supply, the system has an option board fan and four CPU fans. The four CPU fans are redundant in configuration. This means if one fan fails, its associated fan changes its rotating speed to high. There are no serviceable components inside the power supply. If the power supply is opened, the manufacturer's warranty is voided.