Error Messages - Zenith Z-171 Series Service Manual

Page
6-2
System Checkout and Troubleshooting
The system checkout procedure forces the technician to check all areas
of the computer. Many faults present visual indications (video problems,
error messages, etc.) of the problem. Experienced technicians may be
able to interpret these indications without using this whole procedure.
Error messages, described in Table 6-1 can isolate defective modules.
Table 6-1: Error Messages
MESSAGE POSSIBLE PROBLEM
+ + + CPU failure! + + +
+ + + ERROR: ROM checksum failure! + + +
These two messages indicate that the CPU logic may be
malfunctioning. Replace the main logic board.
+ + +ERROR: RAM failure! address: XXX: YYYY, Bit: n, Chip XXX + + +
These messages indicate that the CPU is unable to read
or write to the RAM or video RAM. Check to see if the
memory board is properly seated. The chip number dis-
played is the number of the chip that has failed. Replace
the chip.
+ + + Error: Timer Interrupt failure! + + +
This message indicates the possible failure of interrupt con-
trol and/or timing logic on the main board. Refer to Chapter
5 and make sure the configuration switches and jumpers
are correctly set for the options that may be connected to
the computer. Also, check that the timer chip is properly
installed. If that does not correct the problem, replace the
main board.
+ + +DISK ERROR: Drive not ready! + + +
This message usually appears when the system attempts
to boot the operating system from a disk and there is not
a disk in the disk drive. This message may also appear
due to a faulty disk or floppy disk controller circuit on the
main board. Check to make sure that the cardboard inserts
have been removed from the disk drives. Be sure that there
is a disk in the drive, that it is inserted correctly and that
the drive latch is closed.
If
a disk is properly inserted ill
the drive, try another disk or try booting from the other
disk drive.