Acer Extensa 450 Maintenance Manual

							5
Troubleshooting Procedures
5.1 General
This section provides the following information:
·Overview of the fault isolation process
·Guidelines for isolating computer malfunctions to replaceable subassemblies 
·Instructions for executing diagnostics and interpreting error messages. 
5.2  Overview of Fault Isolation Process
The fault isolation process (summarized in Figure 5-1) consists of the following: 
·Quick Check of the following:
·Notebook power system (including battery packs and AC Adapter
connections)- See Paragraph 5.4.
·Switch settings (ensure Power
 switch is On, and press Standby
switch to ensure that Notebook is not in Standby mode; press Shift
to ensure the notebook is not in Auto-Suspend mode. 
·All external cabling (if any)
·Check LCD Contrast adjustment (Dual Scan version only)
·Record and attempt to resolve any displayed error messages/LED indications
(See Paragraph 5.3 and Table 5-1)
Record and attempt to resolve any series of beeps emitted from the notebook
indicating test failure (See Table 5-2)
  
Troubleshooting 
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							START
COMPUTER
TROUBLE
INDICATION
?
DEAD
COMPUTER
SYMTOMS
?
RUN
SELF TEST
ERROR
MESSAGE
?
MODEM
PROBLEM
?
RUN
DIAGNOSTICS
DIAGNOSTICS
ERROR MSG
?
NOYES NOYES
SEE PARAGRAPH
5.3.5 NOYES
SEE PARAGRAPH
5.3.4
NO
SEE
PARAGRAPHS
5.3.1 & 5.3.2 NOWHEN POWER SWITCH
SET TO ON,, NO
INDICATION OF POWER;
SCREEN DARK, STATUS
LEDs EXTINGUISHED
SET POWER SWITCH
TO ON. SELFTEST
AUTOMATICALLY RUNSYES
See Appendix D
(PC Doctor)
Figure 5-1  Troubleshooting Flowchart
   
5-2 Troubleshooting 
						

							·Try rebooting the system (CTRL-ALT-DEL); restore system from diskettes, if
necessary.
·If the computer is capable of running the Setup program; check the serial and
parallel port configurations, and other features that may affect system
operation.
·Run Diagnostics to further isolate problem area (See Paragraph 5.3.5).
·For indicated hardware failures, cycle power and repeat self test to verify that a
hard failure has occurred. 
·Remove and replace suspect hardware (as described in Section 6 of this
manual) and retest the system using the diagnostic tests as described in
paragraph 5.3.5.
The detailed block diagram, shown in Figure 5-2, is useful in performing fault
analysis of various internal subsystems. For example, an LCD hardware problem
can be traced to either the LCD, Inverter Board, VR Board, or Battery Board. Other
subsystem problems can be isolated in a similar fashion using the detailed block
diagram as a troubleshooting tool. 
5.3 Troubleshooting Procedures
The built-in self test program and the disk resident diagnostics program (PC-Doctor)
are useful tools in computer troubleshooting. However, if the computer has a power,
keyboard or display problem, you first solve this problem before running
diagnostics. If the computer powers up and displays messages on the LCD or emits
a series of beeps, skip to Paragraph 5.4.3 for further instructions. 
5.3.1  Troubleshooting a Power Supply Problem
If the computer does not power up when the Power Switch is set to the ON position,
you most likely have a malfunction in the power subsystem (loss of power at the AC
Outlet, faulty AC Adapter, discharged Battery Packs, or faulty Power Supply Board).
With a power problem, all LEDs are extinguished, the LCD screen is blank, the
system does not respond when the standby switch several times consecutively and
no drive activity can be heard. The computer is unable to load software and
displays no visible signs of activity. 
To fault isolate a power problem, check the following:
·AC Adapter and Battery- Plug in the AC adapter and double check all
connections on the Adapter and computer. Ensure that the Notebook Power
switch is set to the On position and that the system is not in Standby or sleep
mode. 
·Measure the voltage at the AC Outlet or plug in a known good appliance (EG. a
lamp) to verify that voltage is present. If the voltage is O.K., try replacing the
AC Adapter
·Check to see that the battery pack is installed correctly (try using a recharged
battery pack if batteryis discharged).
  
Troubleshooting 
5-3 
						

							·If the AC outlet voltage, AC Adapter, and battery packs test normal but the
computer will not power up, replace the Power Supply Board and/or Battery
Board as described in Section 6.
 
5.3.2  Troubleshooting a Display Problem
If the LCD remains blank when you turn on the computer, and the status indicators
light, check the following controls on the display (See Figure 3-1):
Figure5-2  Troubleshooting Block Diagram
   
5-4 Troubleshooting 
						

							·LCD standby mode - If the LCD backlight remains off, even with the Contrast
Control set to its highest position, the LCD may be in Standby Mode
. Press the
Standby
 or Power
 button to power up the system.
·Notebook Set for External Monitor- use CMOS Setup to reset notebook. 
·LCD - Replace the cover-display assembly as described in Section 6 of this
manual. 
·Low battery - Use a fully charged battery.
5.3.3  Fault Isolation Using Selftest 
When the computer is first powered up, it automatically performs a self-test of its
central hardware and memory functions. During self-test (which lasts for a few
seconds), the display shows copyright and version number information.
nNote:  Some procedures in this paragraph require you to use keystroke se-
quences, such as 
Ctrl-Alt-Del. To execute a keystroke sequence such as
this, you must press all three keys simultaneously.
5.3.3.1   Self Test Error Messages
Upon successful completion of the self-test, the computer automatically loads its
operating system and other built-in utilities. If the self-test fails to complete
successfully, the display shows one of the error messages described in Appendix A. 
5.3.4  PCMCIA Modem Problems
If an optional PCMCIA modem does not work properly, check the following items:
·Proper installation of any PCMCIA options (check Modem settings under
Control Panel).
·Dialing problem or wrong number - Try dialing a number that you have
previously dialed successfully.
·Faulty phone line - Connect a telephone to the line and listen for a dial tone.
·Software program - Check to ensure that you have installed the software
correctly.
  
Troubleshooting 
5-5 
						

							5.3.5  Fault Isolation Using Diagnostics 
PC-Doctor supplied with the Extensa 450 Series Notebooks is a powerful
diagnostics tool that can help you scan an internal RAM system for viruses,
determine the hardware configuration of a local or remote system, benchmark its
performance, analyze the performance of all subsystems, and perform a suite of
interactive and non-interactive tests on attached devices. The test results are stored
in a log which can be printed out (by pressing F2) or saved in a disk file (by pressing
F3). 
Features of the diagnostic program are accessed through a series of pull-down
menus and basic keyboard keys (cursor keys to move highlighted pointer, Enter key
to select a highlighted feature, ESC key to cancel a function and move back one
level. 
PC-Doctor is typically user friendly but if you don’t understand a feature,
context-sensitive “help” information is available at any time by pressing the F1
function key; pressing the F1
 function key twice accesses the online Technical
Reference Manual for PC-Doctor. 
 A powerful set of utilities within PC-Doctor (that can be run locally or remotely)
simplify the task of determining system configuration data, allocating and using
system memory, IRQ and DMA use, what device drivers are installed, what COM
and LPT ports are assigned and what ports are available, identifying partitioning
data for fixed disk drive(s), determining the VGA setup information, reading the
software interrupts/interrupt vectors, etc.
Functionally, PC-Doctor includes the following: 
·Group of nine non-Interactive diagnostic tests that perform a non-destructive
test of the major hardware functions in the notebook (Processor, Memory,
System board, video section, serial and parallel ports (when loopback adapters
are installed), hard disk and floppy disk.
·Group of seven Interactive tests (require operator input) for testing the
keyboard, video sections, sound subsystem, mouse, joystick, diskette drive,
printer subsystem and SCSI/CD-ROM Drive subsystems.
·Utility that provides detailed system information such as configuration data,
allocation and use of system memory, IRQ and DMA use, what device drivers
are installed, what COM and LPT ports are assigned and what ports are
available, partitioning data for fixed disk drive(s), VGA setup information,
software interrupts and interrupt vectors. 
·Group of special purpose utilities to run other tests from PC-Doctor, perform a
virus scan of the internal RAM system, edit configuration files, surface scan
hard drives, measure system performance, open a DOS prompt, provides
terminal access to devices connected to serial ports, supports memory debug
operations, enables remote operations, permits deep discharge of notebook
batteries and provides an extensive test reporting function.
The PC-Doctor diagnostic program contains a group of nine non-Interactive
diagnostics, available from the Diagnostics
 heading in the main menu, that
permits testing various hardware sections without operator input. You can select
one, several, or all tests from the Diagnostics menu. These tests are
non-destructive; the serial and parallel port tests require disconnecting external
   
5-6 Troubleshooting 
						

							devices from your notebook and installing loopback plugs. The Non-Interactive test
categories include: 
·CPU and Co-Processor Tests
·Base RAM memory test
·System Board test
·Video Test
·Com1 and LPT1 serial port tests
·Parallel Port Test
·Fixed Disk test
·Diskette Drive tests
·Other devices (Sound card, PCMCIA options, etc.)
Interactive Tests 
The PC-Doctor diagnostic test includes a suite of seven Interactive tests that require
operator input during the course of the test. The Interactive Tests
 category
includes: 
·Keyboard
- tests the keyboard keys, LEDs and repeat function 
·Video
-tests the LCD and external VGA character sets, and colors. 
·Speaker
-tests the volume response at different frequencies.
·Mouse
-tests the mouse driver, buttons and functionality
·Joystick
- calibrates the external joystick connected to the system
and tests the joystick buttons
·Diskette Drive
- checks diskette drive functionality
·Maximum System Load
- thoroughly exercises system to the
maximum extent possible for performing system “burn-in and test
·Printer Test
- tests the operation of a connected printer
·SCSI Test
- sends test codes to attached SCSI devices (requires use
of a Docking System with SCSI)
·CD-ROM Test
- checks out any attached CD-ROM Drive (requires
attachment of a Docking System with CD-ROM capability)
  
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5-7 
						

							Supporting Online documentation 
The PC-Doctor Diagnostic contains the following online information sources: 
·Online Technical Manual- selected at any time by pressing F1 key twice or by
clicking on the Question Mark in the upper left hand corner of any PC-Doctor
Menu
·On-line Help system that provides context sensitive information from every
PC-Doctor screen- accessed by pressing F1 key once (pressing F1 twice gets
you into the online manual)
5.3.5.1    User Interface to PC-Doctor
PC-Doctor is structured as a text-mode, windowed user interface with pull-down
menus. Program operation requires the use of the following keys:
·Cursor Keys- move the highlighted pointer
·ENTER Key- Selects the highlighted option
·ESC Key- Cancels current function and goes back one step
·F1 Key- Activates the context-sensitive help feature (pressing F1 twice in a row
calls up the online Technical Reference Manual for PC-Doctor)
Scrolling windows, which show the results of various operations, use the following
keys: 
·Page Up/Page Down- moves the screen one page at a time
·F2- Prints the log to PRN
·F3- saves the log to a file
You can also use the mouse or Point to interact with PC-Doctor. The leftmost Select
key is used to choose objects (menu entries and action codes typically enclosed in
brackets). The rightmost Select
 key is equivalent to the ESC key which takes you
back to your previous step. 
5.3.5.2   Creating a Bootable Floppy Diskette
Prior to using PC-Doctor, create a bootable floppy diskette using the following
procedure: 
1.     Power up the unit; when unit displays message, Starting Windows 95, press
F8. Choose Command Prompt Only from menu.
2.
       Using DOS, format a floppy diskette. 
3.     From the A:
 prompt, copy the basic MS-DOS files to the diskette using the
following command: 
Format A: /F:1440 /S 
   
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							Where the value 1440 is the capacity of the diskette (1.44 MB in this example). 
4.     Get into the PC-Doctor directory ( type CD C:\PCDR 
and press Enter
)
5.       Copy the PC-Doctor files to the bootable diskette using the following
command:
 XCOPY C:. A:.
After completion of this procedure, you should have a bootable diskette containing
PC-Doctor. 
5.3.5.3    Running PC-Doctor 
PC-Doctor is a DOS-resident program that can be run from either hard disk or from
the bootable diskette you previously created.   
1
. From the C: prompt change directory (type CD C:\PCDR
) and press Enter
 
2
.    The Diagnostics Program loads into system memory, and the LCD displays the
diagnostics Header. 
nNote:  There are a number of command-line switches that can be entered
when starting up PC-Doctor to enable automatic virus scanning, enable
loopback testing of serial/parallel ports, work from the remote menu if per-
forming remote operations, etc. To get a listing of the available command-
line switches, startup PC-Doctor with the following command: 
PCDR /? and press Enter
.
nNote:  If PC-Doctor detects a virus, it will stop with an error message. You
must then use one of the standard virus detection and removal programs to
remove the virus. 
5.3.5.4    Quitting PC-Doctor
To exit PC-Doctor, Select the Quit
 pull down menu and then select the Quit to DOS
option. 
nNote:  For additional information, press 
F1 twice to access the online Refer-
ence manual for PC-Doctor. 
  
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5-9 
						

							6
Field Service
6.1  Introduction
This section contains preventive and corrective maintenance procedures for the
Extensa 450 Series Notebook Computers. The first part of the section describes the
computer cleaning procedures and preferred handling procedures for sensitive
components (e.g. disk drives, batteries).
The second part of the section identifies all field replaceable parts; the remainder of
the section contains removal and replacement procedures for the field replaceable
parts. 
6.2   Preventive Maintenance
Preventive maintenance is limited to cleaning the plastic case, the keyboard, and
the display screen. 
6.2.1   Cleaning the Computer
When it is necessary to clean the plastic case and keyboard, use a soft, lint-free
cloth, slightly dampened with a mild detergent solution or use the contents of any
commercially available computer cleaning kit.
cCaution: Never use alcohol, petroleum-based solvents, or harsh deter-
gents to clean your computer. Also never spray any liquids directly on
the computer case, keyboard, or screen. If the liquid-crystal display
(LCD) screen has become smeared or dusty, clean the screen by first ap-
plying a mild glass cleaner to a soft, clean, lint-free cloth, and gently
wipe the glass. Never apply liquids directly on the screen surface.
cCaution : Do not use paper towels to clean the display screen. Paper can
scratch the display screen matte.
 
 Field Service   6-1