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Maintenance and Troubleshooting 4-9
Table 4-2 System Error Messages
Message
Description
Address Line Short
Error in the address decoding circuitry on the system board.
Cache Memory Failure, Do
Not Enable Cache
Cache memory is defective. Replace the CPU module.
CMOS Battery Failed
CMOS RAM battery power is low. Replace the battery (see
battery replacement at the end of this section).
CMOS Checksum Invalid
After CMOS RAM values are saved, a checksum value is
generated for error checking. The previous value is different
from the current value. Run Setup (see Section 2).
CMOS System Options Not
Set
The values stored in CMOS RAM are either corrupt or
nonexistent. Run Setup (see Section 2).
CMOS Time and Date Not Set
Run Setup to set the date and time (see Section 2).
Diskette Boot Failure
The boot disk in drive A: is corrupt and cannot be used to boot
the system. Use another boot disk and follow the screen
instructions.
DMA Controller Error
Error in the DMA controller.
Drive Not Ready Error
The BIOS cannot communicate with the diskette drive. Power
off the system and check all connections.
Floppy Disk Controller Failure
The BIOS cannot communicate with the diskette drive
controller. Power off the system and check all connections.
Floppy Drive A: Failure
The BIOS cannot access the diskette drive A:. Power off the
system and check all connections.
Floppy Drive B: Failure
The BIOS cannot access the diskette drive B:. Power off the
system and check all connections.
Gate - A20 Error
Gate A20 on the keyboard controller is not working. Call for
service.
Invalid Boot Diskette
The BIOS can read the disk in diskette drive A:, but cannot
boot the system. Use another boot diskette.
Keyboard Controller Error
The keyboard controller has failed during POST.
Keyboard is Locked...Please
Unlock It.
Keyboard lock on the system is engaged. The system must be
unlocked to continue.
Keyboard Stuck Key Detected
There is a key pressed down on the keyboard.
Master DMA Controller Error
Error in the master DMA channel.
Master Interrupt Controller
Error
Master Interrupt Controller failed during POST.
Memory Size Decreased
The amount of memory on the system board is less than the
amount in CMOS RAM. Check for mismatched SIMM sizes.
(All SIMMs must be the same size within a bank.) Run Setup
(see Section 2).
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