Toshiba Libretto 50CT/70CT Manual

							2.5  Floppy Disk Drive (FDD) Troubleshooting2  Troubleshooting Procedures2-18Libretto 50CT/70CT Maintenance ManualEEhWrite buffer error 
						

							2  Troubleshooting Procedures2.5  Floppy Disk Drive (FDD) TroubleshootingLibretto 50CT/70CT Maintenance Manual2-19Check 1If the following message is displayed, disable the write protect tab on the floppy
disk.  If any other message displays, perform Check 2.
Write protected
Check 2Make sure the floppy disk is formatted correctly.  If it is, go to Procedure 3.
Procedure 3Connector Check and Replacement CheckThe FDD, cable, and PC card is a single unit. Install the PC card in the computer, then begin
with Check 1 below.Check 1Make sure the PC card is properly connected to the system board.If the connection is loose, reinstall the PC card and repeat Procedure 2. If there is
still an error, go to Check 2.
Check 2The FDD may be defective or damaged.  Replace the FDD with a new one.  If the
FDD is still not functioning properly, perform Check 3.
Check 3Replace the system board with a new one following the steps in Chapter 4,
Replacement Procedures. 
						

							2.6  Hard Disk Drive (HDD) Troubleshooting2  Troubleshooting Procedures2-20Libretto 50CT/70CT Maintenance Manual2.6 Hard Disk Drive (HDD) Troubleshooting
To determine if the hard disk drive is functioning properly, do the procedures below starting
with Procedure 1.  Continue with the other procedures as instructed.
Procedure 1:Partition Check
Procedure 2:Message Check
Procedure 3:Format Check
Procedure 4:Diagnostic Test Program Execution Check
NOTES:  1.  The contents of the hard disk will be erased when the HDD troubleshooting procedures are executed.  Transfer the contents of the hard disk to floppy disk or other device. If the customer has not or cannot perform the backup, create backup disks as described below.2.  Check to see if the Microsoft Create System Disks Tools (MSCSD.EXE) still exists in the System Tools Folder. (This tool can be used only once.) If it exists, use it to back up the preinstalled software, then use the Backup utility in the System Tools folder to back up the entire disk, including the user’s files.Refer to the operating system instructions.Procedure 1Partition Check
Insert the Toshiba MS-DOS system disk, turn the computer on, then perform the following
checks:
Check 1Type C: and press Enter.  If you cannot change to drive C, go to Check 2.  If you
can, go to Procedure 2.
Check 2Type FDISK and press Enter.  Choose Display Partition Information from the
FDISK menu.  If drive C is listed, go to Check 3.  If not, return to the FDISK
menu and choose the option to create a DOS partition on drive C. Recheck the
system.  If the problem still exists, go to Procedure 2.
Check 3If drive C is listed as active in the FDISK menu, go to Check 4.  If not, return to
the FDISK menu and choose the option to set the active partition for drive C.
Recheck the system.  If the problem still exists, go to Procedure 2.
Check 4Remove the system disk from the FDD and cold-boot the computer.  If the
problem still exists, go to Procedure 2.  Otherwise, the HDD is operating normally. 
						

							2  Troubleshooting Procedures2.6  Hard Disk Drive (HDD) TroubleshootingLibretto 50CT/70CT Maintenance Manual2-21Procedure 2Message Check
When the HDD does not function properly, some of the following error messages may appear
on the display.  Start with Check 1 below and perform the other checks as instructed.
Check 1If any of the following messages display, go to Check 5.  If not, go to Check 2:HDD ERROR
or
HDD #x ERROR
(After 5 seconds this message will disappear.)Check 2If either of the following messages displays go to Check 3.  If not, go to check 5.
Insert system disk in drive
Press any key when ready .....
or
Non-System disk or disk error
Replace and press any key
Check 3Use the Toshiba MS-DOS system disk to install a system program on the hard
disk, using the SYS command.
If the following message displays, the system program has been transferred to the
HDD.  Restart the computer.  If the error message still displays, go to Check 4.
System transferred
Check 4If the HDD is firmly connected to the system board, go to Check 5.
Check 5The HDD connector may be defective or damaged. Replace the HDD connector
with a new one following the steps in Chapter 4, Replacement Procedures. If the
HDD is still not functioning properly, go to Procedure 3.
Procedure 3Format Check
The HDD is formatted using the low level format program and the MS-DOS FORMAT
program.  To format the HDD, start with Check 1 below and do the other steps as required.
Check 1Format the hard disk using FORMAT C:/S/U to transfer the system program to
the HDD.  If the following message displays, the HDD is formatted.
Format complete
If any other error message displays, refer to the Toshiba MS-DOS Manual for
more information and do Check 2. 
						

							2.6  Hard Disk Drive (HDD) Troubleshooting2  Troubleshooting Procedures2-22Libretto 50CT/70CT Maintenance ManualCheck 2Use the Toshiba MS-DOS system disk to partition the hard disk, using the FDISK
command.
Check 3Using the Diagnostic Disk, format the HDD with a low level format option.  Refer
to Chapter 3, Tests and Diagnostics for more information about the diagnostics
program.
If the following message displays, the HDD low level format is complete.
Partition and format the HDD using the MS-DOS FORMAT command.
Format complete
If you cannot format the HDD using the Tests and Diagnostics program, go to
Procedure 4.
Procedure 4Diagnostic Test Program Execution Check
The HDD test program is stored on the Diagnostics Disk.  Do all of the HDD tests in the
Hard Disk Drive Test.  Refer to Chapter 3, Tests and Diagnostics, for more information about
the HDD test program.
If an error is detected during the HDD test, an error code and status will display; do Check 1.
The error codes and statuses are listed in Table 2-6.  If an error code is not generated, the
HDD is operating properly. 
						

							2  Troubleshooting Procedures2.6  Hard Disk Drive (HDD) TroubleshootingLibretto 50CT/70CT Maintenance Manual2-23Table 2-6  Hard disk drive error codes and statuses
CodeStatus01hBad command02hBad address mark03hWrite Protected04hRecord not found06hHDC not reset08hDMA overrun error09hDMA boundary error10hCRC error20hFDC error40hSeek error60hFD not in drive80hTime out errorEEhWrite Buffer errorFFhData compare errorCheck 1Replace the HDD unit with a new one following the instructions in Chapter 4,
Replacement Procedures. If the HDD is still not functioning properly, do Check 2.
Check 2Replace the system board with a new one following the instructions in Chapter 4. 
						

							2  Troubleshooting Procedures2.7  Keyboard TroubleshootingLibretto 50CT/70CT Maintenance Manual2-232 
2.7 Keyboard Troubleshooting
This section describes how to determine if the keyboard is functioning properly.  To
troubleshoot the keyboard, start with Procedure 1 and continue with the other procedure as
instructed.
The procedures described in this section are:
Procedure 1:Diagnostic Test Program Execution Check
Procedure 2:Connector and Replacement Check
Procedure 1Diagnostic Test Program Execution Check
Execute the Keyboard Test in the Diagnostic Program.  Refer to Chapter 3, Tests and
Diagnostics, for more information on how to perform the test program.
If an error occurs, go to Procedure 2.  If an error does not occur, the keyboard is functioning
properly.
Procedure 2Connector and Replacement Check
The keyboard is connected to the system board by flat cables. These cables or connectors may
be disconnected or damaged. If there is a problem with the keyboard, disassemble the
computer as described in Chapter 4, Replacement Procedures, and do Check 1.
Check 1Be sure the following cables are not damaged and are connected to the system
board.If the cables are damaged, replace the keyboard with a new one.  If the cable is
disconnected, firmly connect it.  Do Procedure 1 again.  If the error still exists, go
to Check 2.
Check 2The system board may be damaged.  Replace the system board with a new one.
Refer to Chapter 4 for more information. 
						

							2.8  Pointing Device Troubleshooting2  Troubleshooting Procedures2-24Libretto 50CT/70CT Maintenance Manual2.8 Pointing Device Troubleshooting
This section describes how to determine if the pointing device is functioning properly. To
troubleshoot the pointing device, start with procedure 1 and continue with the other
procedure as instructed.
Procedure 1:Diagnostic Test Program Execution Check
Procedure 2:Connector and  Replacement Check
Procedure 1Diagnostic Test Program Execution Check
Execute the Pointing Device Test in the Diagnostic Program.  Refer to Chapter 3, Tests and
Diagnostics, for information on how to do the test program.  If an error occurs, go to
Procedure 2.  If an error does not occur, the pointing device is functioning properly.
Procedure 2Connector and Replacement Check
The pointing device is connected to the system board by flat cables.  These cables or
connectors may be disconnected or damaged.  If there is a problem with the pointing device,
disassemble the computer as described in Chapter 4, Replacement Procedures, and do   Check
1.
Check 1The AccuPoint board or flat cables may be damaged.  Replace the AccuPoint
board or flat cables with new ones. 
						

							2  Troubleshooting Procedures2.9  Display TroubleshootingLibretto 50CT/70CT Maintenance Manual2-252.9 Display Troubleshooting
This section describes how to determine if the display is functioning properly.  Start with
Procedure 1 and continue with other procedures as instructed.
Procedure 1:Diagnostic Test Program Execution Check
Procedure 2:Connector Check
Procedure 3:Replacement Check
Procedure 1Diagnostic Test Program Execution Check
The Display Test program is stored on the Diagnostics Disk.  This program checks the display
controller on the system board.  Insert the Diagnostics disk into the floppy disk drive, turn on
the computer, and run the test.  Refer to Chapter 3, Tests and Diagnostics, for details.
If an error is detected, go to Procedure 3.  If an error is not detected, the display is
functioning properly.
Procedure 2Connector Check
The Display unit has an LCD module, FL, and FL inverter board.
Disassemble the display unit and check the cable connections. Refer to Chapter 4,
Replacement Procedures, for more information about how to disassemble the computer.
If any cable is not connected, firmly reconnect it and repeat Procedures 1 and 2.  If the
problem still exists, go to Procedure 4.
Procedure 3Replacement Check
The FL, FL inverter board, LCD module, LCD flat cable, and system board are connected to
the display circuits. Any of these components may be damaged.  Refer to Chapter 4,
Replacement Procedures, for instructions on how to disassemble the computer and then do
the following checks:
If the FL does not light, go to Check 4.
If characters are not displayed clearly, go to Check 3.
If some screen functions do not operate properly, go to Check 3.
Check 1Replace the LCD flat cable with a new one and test the display again.  If the
problem still exists, go to Check 2. 
						

							2.9  Display Troubleshooting2  Troubleshooting Procedures2-26Libretto 50CT/70CT Maintenance ManualCheck 2Replace the LCD module with a new one and test the display again. If the problem
still exists, go to Check 3.
Check 3Replace the FL inverter board with a new one and test the display again. If the
problem still exists, go to Check 4.
Check 4Replace the FL with a new one and test the display again. If the problem still
exists, go to Check 5.
Check 5The system board may be damaged. Replace the system board with a new one.