Acer Aspire 4520 4220 4520G 4220G User Manual

							
Chapter 365
Removing the Touchpad Cable
6.Disconnect the touchpad cable from the touchpad module as shown.
Disassembling the Main Board
Removing the USB Board
1.Remove the two screws fastening the USB board.
2. Remove the USB board.
Removing the MDC Card Module
3.Remove the screw fastenin g the MDC card module.
4. Remove the MDC card module. 
						

							
66Chapter 3
Removing the Thermal Module and System Fan
5.Unscrew the four spring screws and remove  the two screws fastening the thermal module.
6. Disconnect the system fan cable as shown.
7. Remove the thermal m odule and system fan.
Removing the CPU
8.Use a flat screwdriver to release th e CPU lock (Turn counter clockwise).
9. Remove the CPU from the CPU socket carefully. 
						

							
Chapter 367
Disassembling the LCD Module
1.Remove the six screw rubbers as shown.
2. Then remove the six screws fastening the LCD bezel.
3. Detach the LCD bezel from the LCD module carefully.
4. Remove the four screws holding the LCD.
5. Detach the two inverter cable con nectors from the inverter board.
6. Disconnect the CCD cable connector from the CCD board.
7. Take out the LCD from the LCD panel.
8. Remove the two screws fastening the left LCD bracket and detach it. 
						

							
68Chapter 3
9.Remove the two screws fastening the right LCD bracket and detach it.
10. Disconnect the LCD cable from the LCD.
11 . Detach the microphone cable from the LCD cover and remove the microphone.
12. Remove the CCD from the LCD cover as shown.
Disassembling the External Modules
Disassembling the HDD Module
1.Remove the two screws fastening the bracket to the HDD module.
2. Remove the bracket.
Disassembling the ODD Module
1.Remove the two screws holding the optical bracket.
2. Then remove the optical bracket from the optical disk drive. 
						

							
Chapter 469
Use the following procedure as a guide for computer problems.
NOTE: The diagnostic tests are intended to test only Acer  products. Non-Acer products, prototype cards, or 
modified options can give false e rrors and invalid system responses.
1. Obtain the failing symptoms in as much detail as possible.
2. Verify the symptoms by attempting to re-create the fa ilure by running the diagnostic test or by repeating 
the same operation.
3. Use the following table with the verified symptom to determine which page to go to.
Symptoms (Verified)Go To
Power failure (The power indicator does not go 
on or stay on). “Power System Check” on page 71
POST does not complete. No beep or error 
codes are indicated. “Power-On Self-Test (POST) Error Message” on 
page 74
“Undetermined Problems” on page 86
POST detects an error and displayed messages 
on screen. “Error Message List” on page 75
Other symptoms (i.e. LCD display problems or 
others). “Power-On Self-Test (POST) Error Message” on 
page 74
Symptoms cannot be re-created (intermittent 
problems). Use the customer-reported symptoms and go to 
“Power-On Self-Test (POST) Error Message” on 
page 74
“Intermittent Problems” on page 85
“Undetermined Problems” on page 86
Troubleshooting
Chapter 4 
						

							
70Chapter 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.
NOTE:  Make sure that the diskette does not have more than on e 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:
1. Boot from the diagnostics diskette and start the diagnostics program.
2. See if FDD Test is passed as the program runs to FDD Test.
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/DVD-ROM module.
2. Replace the external diskette drive/CD-ROM module.
3. Replace the main board.
External CD-ROM Drive Check
Do the following to isolate the problem to a controller,  drive, or CD-ROM. Make sure that the CD-ROM does 
not have any label attached to it. The label can caus e damage to the drive or can cause the drive to fail.
Do the following to select the test device:
1. Boot from the diagnostics diskette and start the diagnostics program.
2. See if CD-ROM Test is passed when  the program runs to CD-ROM Test.
3. Follow the instructions in the message window.
If an error occurs, reconnect the connector on  the System board. If the error still remains:
1. Reconnect the external diskette drive/CD-ROM module.
2. Replace the external diskette drive/CD-ROM module.
3. Replace the main 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 correctly se ated in the connector on the system board.
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. Do not replace a 
non-defective FRU:
1. Reconnect the keyboard cables.
2. Replace the keyboard.
3. Replace the main board.
The following auxiliary input devices are supported by this computer:
TNumeric keypad
TExternal keyboard 
						

							
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If any of these devices do not work, reconnect the cable connector and repeat the failing operation. 
Memory check
Memory errors might stop system operations, show  error messages on the screen, or hang the system.
1. Boot from the diagnostics diskette and start the di agnostic program (please refer to main board).
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.
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 co mputer 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 ba ttery pack; then check that power is supplied by 
the battery pack.
If you suspect a power problem, see the approp riate power supply check in the following list:
T“Check the Power Adapter” on page 72
T“Check the Battery Pack” on page 73 
						

							
72Chapter 4
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 System board.
TIf the problem is not corrected, s ee “Undetermined Problems” on page 86.
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 power-on indicator does not light up, check  the power cord of the power adapter for correct 
continuity and installation.
4. If the operational charge does not work, see “Check the Battery Pack” on page 73. 
Pin 1: +19 to +20.5V
Pin 2: 0V, Ground 
						

							
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Check the Battery Pack 
To check the battery pack, do the following:
From Software:
1.Check out the Power Management in Control Panel
2. In Power Meter, confirm that if the parameters sh own 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 prob lem is on recharging or discharging. 
From Hardware:
1. Power off the computer. 
2. Remove the battery pack and measure  the voltage between battery terminals 1(+) and 6(ground). See the 
following figure
3. If the voltage is still less than 7.5 Vdc  after recharging, replace the battery. 
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 indicato r 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 li ght up, replace the battery pack. If the charge indicator still does not light 
up, replace the DC/DC charger board. 
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 cables.
2. Replace the touchpad.
3. Replace the system board.
After you use the touchpad, the pointer drifts on the scr een 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. 
						

							
74Chapter 4
Power-On Self-Test (POST) Error Message 
The POST error message index lists the error message and their possible causes. The most likely cause is 
listed first.
NOTE: Perform the FRU replacement or actions in the s equence shown in FRU/Action column, if the FRU 
replacement does not solve the proble m, 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, se e “Undetermined Problems” on page 86.
The following lists the error messages that the BIOS di splays on the screen and the error symptoms classified 
by function. 
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. 
NOTE:  If the system fails after you make changes in the B IOS Setup Utility menus, reset the computer, enter 
Setup and install Setup defaults or correct the error.