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System Check Procedures
External Diskette Drive Check
Do the following steps to isolate the problem to a controller, driver, or diskette. A write-enabled, diagnostic
diskette is required.
NOTE: Make sure that the diskette does not have more than one label attached to it. Multiple labels can cause
damage to the drive or cause the drive to fail.
Do the following to select the test device. See “System Diagnostic Diskette” on page 52 for details.
1.The FDD heads can become dirty over time, affecting their performance. Use an FDD cleaning kit to clean
the heads. If the FDD still does not function properly after cleaning, go to next step.
2.Boot from diagnostic program (see“System Diagnostic Diskette” on page 52)
3.If an error occurs with the internal diskette drive, reconnect the diskette connector on the main board.
If the error still remains:
1.Reconnect the external diskette drive module.
2.Replace the external diskette drive module.
3.Replace the main board.
External CD-ROM/DVD-ROM Drive Check
Do the following to isolate the problem to a controller, drive, or CD-ROM/DVD-ROM. Make sure that the CD-
ROM does not have any label attached to it. The label can cause damage to the drive or can cause the drive to
Do the following to select the test device:
1.Insert an audio CD into the CD/DVD drive. If the CD/DVD drive can read the data from the audio CD. The
drive does not have problem, then go to next step. If the CD/DVD LED on the front panel does not emit
light as it read the data from the audio CD, then go to next step. However, if the CD/DVD drive can not
read data from the audio CD, you may need to clean the CD/DVD drive with a CD/DVD drive cleaning
2.Make sure that the appropriate driver has been installed on the computer for the CD/DVD drive.
3.Boot from the diagnostics diskette and start the diagnostics program (refer to “System Diagnostic
Diskette” on page 52.)
4.See if CD-ROM Test is passed when the program runs to CD-ROM/DVD-ROM Test.
5.Follow the instructions in the message window.
If an error occurs, reconnect the connector on the main board. If the error still remains:
1.Reconnect the CD-ROM/DVD-ROM module.
2.Replace the CD-ROM/DVD-ROM module.
3.Replace the main board.
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Keyboard or Auxiliary Input Device Check
Remove the external keyboard if the internal keyboard is to be tested.
If the internal keyboard does not work or an unexpected character appears, make sure that the flexible cable
extending from the keyboard is correctly seated in the connector on the main board.
If the keyboard cable connection is correct, run the Keyboard Test. See “System Diagnostic Diskette” on page
52 for more details.
If the tests detect a keyboard problem, do the following one at a time to correct the problem. Do not replace a
1.Reconnect the keyboard cables.
2.Replace the keyboard.
3.Replace the main board.
The following auxiliary input devices are supported by this computer:
TEmbedded Numeric Keypad
If any of these devices do not work, reconnect the cable connector and repeat the failing operation.
Memory errors might stop system operations, show error messages on the screen, or hang the system.
Currently, we do not provide memory test program. However, if you need to check memory but have no testing
program or diagonositc utility at hand, please go to http://www.passmark.com to download the shareware
“BurnIn Test V.3.0”. You may test the memory with this program under Window XP environment.
NOTE: Make sure that the DIMM is fully installed into the connector. A loose connection can cause an error.
Power System Check
To verify the symptom of the problem, power on the computer using each of the following power sources:
1.Remove the battery pack.
2.Connect the power adapter and check that power is supplied.
3.Disconnect the power adapter and install the charged battery pack; then check that power is supplied by
the battery pack.
If you suspect a power problem, see the appropriate power supply check in the following list:
T“Check the Power Adapter” on page 80
T“Check the Battery Pack” on page 81
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Check the Power Adapter
Unplug the power adapter cable from the computer and measure the output voltage at the plug of the power
adapter cable. See the following figure
1.If the voltage is not correct, replace the power adapter.
2.If the voltage is within the range, do the following:
TReplace the main board.
TIf the problem is not corrected, see “Undetermined Problems” on page 90.
TIf the voltage is not correct, go to the next step.
NOTE: An audible noise from the power adapter does not always indicate a defect.
3.If the DC-IN indicator does not light up, check the power cord of the power adapter for correct continuity
4.If the operational charge does not work, see “Check the Power Adapter” on page 80.
Pin 1: 19V
Pin 2: 0V, Ground
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Check the Battery Pack
To check the battery pack, do the following:
1.Check out the Power Options in control Panel
2.In Power Meter, confirm that if the parameters shown in the screen for Current Power Source and Total
Battery Power Remaining are correct.
3.Repeat the steps 1 and 2, for both battery and adapter.
4.This helps you identify first the problem is on recharging or discharging.
1.Power off the computer.
2.Remove the battery pack and measure the voltage between battery terminals 1(+) and 6(ground).
3.If the voltage is still less than 7.5 Vdc after recharging, replace the battery.
4.If the voltage is within the normal range, run the diagnostic program.
To check the battery charge operation, use a discharged battery pack or a battery pack that has less than 50%
of the total power remaining when installed in the computer.
If the battery status indicator does not light up, remove the battery pack and let it return to room temperature.
Re-install the battery pack.
If the charge indicator still does not emit, replace the battery pack. If the charge indicator still does not light up,
replace the DC/DC charger board.
If the touchpad doesn’t work, do the following actions one at a time to correct the problem. Do not replace a
1.After rebooting, run Touch pad/PS2 Mode Driver.
2.Run utility with the PS/2 mouse function and check if the mouse is working.
3.If the PS/2 mouse does not work, then check if the main board to switch board FPC is connected well.
4.If the main board to switch board FPC is connected well, then check if the touch pad FPC connects to the
main board properly.
5.If there is still an error after you have connected the touch pad FPC to the main board properly, then
replace the touch pad or touch pad FPC. The touch pad or touch pad FPC may be damaged.
6.Replace switch board.
7.If the touch pad still does not work, then replace the FPC on Track Pad PCB.
After you use the touchpad, the pointer drifts on the screen for a short time. This self-acting pointer movement
can occur when a slight, steady pressure is applied to the touchpad pointer. This symptom is not a hardware
problem. No service actions are necessary if the pointer movement stops in a short period of time.
1.Connect an external display to the computer’s external monitor port, the boot the computer. The computer
can automatically detect the external display. Press Fn+ p to switch to the external display.
2.If the external display works fine, the internal LCD may be damaged. Then perform the following steps:
Make sure the DDRRAM module is seated properly. Then run the diplay test again. If the problem
still exists, go to next step.
Replace the inverter board, then run the display test program again. If the problem still occurs, go
on next step.
Replace the LCD module with a new one then run the display test again. If the probelm still
happens, continue next step.
Replace LCD/FL cable with a new one then execute the display diagnostic again. If the problem
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still occurs, continue next step.
Replace the CPU with another of the same specifications. If the problems still occurs, go to next
The main board may be damaged. Replace main board.
3.If the external monitor has the same problem as the internal monitor, the main board may be damaged.
Please insert the diagnostic disk and run the display test program and go through the sub-steps under
To determine if the computer’s built-in speakers are functioning properly, perform the following steps. Before
you start the steps below, adjust the speaker volume to an appropriate level.
1.Try different audio sources. For example, employ audio CD and ditital music file to determine whether the
fault is in the speaker system or not. If not all sources have sound problem, the problem is in the source
devices. If all have the same problem, continue next step.
2.Connect a set of earphone or external speakers. If these devices work fine, go to next step. If not, then the
main board may be defective or damaged. Replace the main board.
3.Follow the disassembling steps in Chapter 3. Esure the speaker cable is firmly connected to the main
board. If the speaker is still a malfunction, go on next step.
4.If the speakers do not sound properly, the speakers may be defective or damaged. Replace the speakers.
If the problem still occurs, then replace the main board.
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