Acer Travelmate 4520 Service Guide

							Chapter 361
2.Release the WLAN antennas from the left and right LCD brackets.
3.Remove the LCD panel from its chassis.  
Removing the LCD-CCD Cable      
1.Peel off the LCD-CCD cable from the bottom edge of the LCD panel.
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							62Chapter 3
2.Detach the adhesive tab on the cables’s LCD connector, then disconnect the cable from the LCD 
panel PCB.
Removing the LCD Panel Brackets      
TRemove the screws securing the LCD panel brackets.
StepPart Number and Type QuantityColorTo r q u e
*M2 x L3 BZN+NYLOK8 Silver1.6 kgf-cm +/-15% 
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							Chapter 363
Removing the Internal Microphone and the CCD Board              
1.Peel off the aluminum foil tabs and acetic tape securing the microphone cable.
2.Carefully remove the internal microphone from the LCD chassis.
3.Remove the CCD board from the LCD chassis. 
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							64Chapter 3
Removing the WLAN Antennas    
1.Peel off the aluminum foil tabs securing the WLAN antennas.
2.Carefully detach the WLAN antenna from the LCD chassis. 
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							Chapter 465
This chapter provides instructions on how to troubleshoot system hardware problems. If the problem can’t be 
resolved using the procedures described here, information for getting online technical assistance is also 
provided. 
Hardware Diagnostic Procedure
IMPORTANT:  The diagnostic tests described in this chapter are only intended to test Acer products. Non-Acer 
products, prototype cards, or modified options can give false errors and invalid system 
responses.
1.Obtain as much detail as possible about the presented failure symptoms. 
2.Verify the symptoms by attempting to re-create the failure through diagnostic tests or by repeating the 
same condition that precedes the symptoms.
3.Refer the table below to determine which corrective action to perform. 
ProblemSymptomSection to Refer to
Power failure The power indicator does light up or 
stay lit.“Power System Check” on page 67
POST failure POST does not complete. No beep or 
error codes issued.“POST Error Message” on page 69
“Undetermined Problems” 
POST detects an error and displayed 
messages on screen.“POST Error Message” on page 69
Specific component 
failure Dysfunctional component symptoms 
(e.g. blurred LCD display).“POST Error Message” on page 69
Intermittent failure Symptoms cannot be re-created Use the customer-reported symptoms 
and go to the “POST Error Message” 
section on page 69.
“Intermittent Problems” on page 80
System Troubleshooting
Chapter 4
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							66Chapter 4
System Check Procedures
External Diskette Drive Check
Do the following to isolate the problem to a controller, driver, or diskette. A write-enabled, diagnostic diskette is 
required.
IMPORTANT:  Make sure that the diskette does not have more than one label attached to it. Multiple labels 
can damage to the drive. 
1.Boot from the diagnostics diskette and start the diagnostics program.
2.Check if the FDD Test is successful (pass).
3.Follow the instructions in the message window.
If an error occurs with the internal diskette drive, reconnect the diskette connector on the system board.
If the error still remains:
1.Reconnect the external diskette drive.
2.Replace the external diskette drive.
3.Replace the system board.
External CD-ROM Drive Check
Do the following to isolate the problem to a controller, drive, or CD-ROM. 
IMPORTANT:  Make sure that the CD-ROM does not have any label attached to it. The label can damage the 
drive.
1.Boot from the diagnostics diskette and start the diagnostics program.
2.Check if the CD-ROM Test is successful (pass).
3.Follow the instructions in the message window.
If an error occurs, reconnect the CD-ROM drive connector on the system board. 
If the error still remains:
1.Reconnect the CD-ROM module.
2.Replace the CD-ROM module.
3.Replace the system board.
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 properly connected to its system board connector (KB1).
If the keyboard cable connection is correct, run the Keyboard Test. 
If the tests detect a keyboard problem, do the following one at a time to correct the problem. 
1.Reconnect the keyboard cable.
2.Replace the keyboard.
3.Replace the system board.
The following auxiliary input devices are supported by this computer:
TNumeric keypad
TExternal keyboard
If any of these devices do not work, reconnect the device cable and check if that corrects the device failure.
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							Chapter 467
Memory Check
Memory errors might stop system operations, display error messages, or cause the system to hang up.
Make sure that the DIMM is properly installed in its slot. A loose connection can cause an error.
If the DIMM connection is correct, run the Doagmpstotics Test. 
1.Boot from the diagnostics diskette and start the Doagmpstotics program.
2.Go to the diagnostic memory in the test items.
3.Press F2 in the test items.
4.Follow the instructions in the message window.
Power System Check
To verify the cause of the power problem, power on the computer using the AC adapter, and then the battery 
pack. 
1.Remove the battery pack.
2.Connect the AC adapter and check if power is supplied.
3.Disconnect the AC adapter and install a fully-charged battery pack, and then check if power is supplied.
t     If the failure is cause by a defective AC adapter, refer to the “Check the AC Adapter” section. 
t     If the failure is cause by a defective battery pack, refer to the “Check the Battery Pack” section.
Check the AC Adapter
Unplug the AC adapter cable from the computer and measure the output voltage at the plug of the AC adapter 
cable. Refer the figure below.
1.If the voltage is not correct, replace the power adapter.
2.If the voltage is within the range, do the following:
a.Replace the system board.
b.If the problem is not corrected, see the section “Undetermined Problems” on page 81.
c.If the voltage is still not corrected, proceed to the next step.
NOTE:  An audible noise from the power adapter does not always indicate a defect.
3.If the power indicator does not light up, check the power cord of the AC adapter for correct continuity and 
installation.
4.If the operational charge does not work, see the “Check the Battery Pack” section on the next page. 
 Pin 1: + 19 to +20.5V
 Pin 2: OV, ground
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							68Chapter 4
Check the Battery Pack  
Check the battery pack via the OS control and by checking the actual battery pack. 
Using the OS control:
1.Open the Power Management setting in the Windows Control Panel
 screen. 
2.On the Power Meter
 tab, confirm that the Current Power Source and Total Battery Power Remaining 
parameters are correct.
3.Repeat steps 1 and 2 using both the battery pack and the AC adapter as the power source.
This will help you identify if the problem is on recharging or discharging. 
Checking the battery pack voltage:
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. 
Checking the battery charge function:
1.Use a discharged battery pack or a battery pack that has less than 50% of the total power remaining when 
installed in the computer. 
2.If the battery charge indicator does not light up, remove the battery pack and allow it to return to room 
temperature, then reinstall the battery pack.
3.If the charge indicator still does not light up, replace the battery pack. 
Touchpad Check
If the touchpad doesn’t work, do the following actions one at a time to correct the problem. Do not replace a 
non-defective FRU:
1.Reconnect the touchpad cable.
2.Replace the touchpad board.
3.Replace the system board.
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.
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							Chapter 469
POST Error Indicators
When POST detects a system failure, it either displays a POST error message, or emits a series of beep 
codes. 
POST Error Message
Whenever a non-fatal error occurs during POST, an error message describing the problem appears onscreen. 
These text messages are displayed in normal video (white text on black background). It shows the details of 
the error.
The POST error message index in this section lists the error messages and their possible causes. The most 
likely cause is listed first. The listed error symptoms classified by function.
NOTE:  Perform the FRU replacement or actions in the sequence shown in FRU/Action column, if the FRU 
replacement does not solve the problem, put the original part back in the computer. Do not replace a 
non-defective FRU.
This index can also help you determine the next possible FRU to be replaced when servicing a computer.
If the symptom is not listed, see “Undetermined Problems” on page 81.
NOTE:  Most of the error messages occur during POST. Some of them display information about a hardware 
device, e.g., the amount of memory installed. Others may indicate a problem with a device, such as 
the way it has been configured. 
IMPORTANT:  If the system fails after you make changes in the Setup Utility menus, reboot the computer, 
enter Setup, then press F9 to load the Setup defaults to correct the error. 
Error Code List 
Error CodeError Message
006 Equipment Configuration Error
Causes:
1. CPU BIOS Update Code Mismatch
2. IDE Primary Channel Master Drive Error
(The causes will be shown before the Equipment 
Configuration Error message)
010 Memory Error at xxxx:xxxx:xxxxh (R:xxxxh, W:xxxxh) 
070 Real Time Clock Error
071 CMOS Battery Bad
072 CMOS Checksum Error
110 System disabled.
Incorrect password is specified.
 Battery Critical Low
In this situation BIOS will issue four short beeps, then shut 
down the system, no message will show.
 Thermal Critical High
In this situation BIOS will shut down the system, no 
message will show.
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							70Chapter 4
Error Message List
Error MessageFRU/Action in Sequence
Failure Fixed Disk Reconnect the hard disk drive to its connector.
Run the Setup Utility, then press F9 to load the system 
defaults.
Hard disk drive
System board
Stuck Key Refer to the “Keyboard or Auxiliary Input Device Check” 
section on page 66. 
Keyboard Error Refer to the “Keyboard or Auxiliary Input Device Check” 
section on page 66.
Keyboard Controller Failed Refer to the “Keyboard or Auxiliary Input Device Check” 
section on page 66.
Keyboard locked - Unlock key switch Unlock external keyboard
Monitor type does not match CMOS - Run 
SetupRun the Setup Utility, then press F9 to load the system 
defaults.
Shadow RAM Failed at offset: nnnn BIOS ROM
System board
System RAM Failed at offset: nnnn DIMM
System board
Extended RAM Failed at offset: nnnn DIMM
System board
System battery is dead - Replace and run 
SetupReplace the RTC battery, then access the Setup Utility to 
reconfigure the system time setttings.
System CMOS checksum bad - Default 
configuration usedRTC battery
Run the Setup Utility to reconfigure the system time settings.
System timer error RTC battery
Run the Setup Utility to reconfigure the system time settings.
System board
Real time clock error RTC battery
Run the Setup Utility to reconfigure the system time settings.
System board
Previous boot incomplete - Default 
configuration usedRun the Setup Utility, then press F9 to load the system 
defaults.
RTC battery
System board
Memory size found by POST differed from 
CMOSRun the Setup Utility, then press F9 to load the system 
defaults.
DIMM
System board
Diskette drive A error Check if the drive matches the diskette type set in the Setup 
Utility.
Refer to the “External Diskette Drive Check” section on 
page 66.
Incorrect Drive A type - run SETUP Check if the drive matches the diskette type set in the Setup 
Utility.
System cache error - Cache disabled System board
CPU ID: System board
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