Acer Aspire 2420 Service Guide

							Chapter 391
10.Disconnect the inverter board cable from its connector, then disconnect the 2P cable on the inverter board 
to remove it. 
11 .Detach the acetic tapes holding the FPC cable from the LCD panel and detach the acetic tape securing 
the FPC connector.  
						

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12.Disconnect the FPC cable from the LCD panel. 
Removing the LCD Brackets
1.See “Removing the Battery Pack” on page 56.
2.See “Removing the SD dummy card” on page 56.
3.See “Removing the ExpressCard dummy card” on page 57.
4.See “Removing the Lower Cover” on page 57.
5.See “Removing the WLAN Board Modules” on page 60.
6.See “Removing the Keyboard” on page 69.
7.See “Removing the LCD Module” on page 70.
8.See “Removing the LCD Bezel” on page 87.
9.See “Removing the LCD module with the Brackets” on page 88.
10.See “Removing the Inverter Board and FPC Cable” on page 90. 
						

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11 .Remove the four screws (G) securing the left and right LCD brackets to remove the brackets. 
Removing the Antennas 
1.See “Removing the Battery Pack” on page 56.
2.See “Removing the SD dummy card” on page 56.
3.See “Removing the ExpressCard dummy card” on page 57.
4.See “Removing the Lower Cover” on page 57.
5.See “Removing the WLAN Board Modules” on page 60.
6.See “Removing the Keyboard” on page 69.
7.See “Removing the LCD Module” on page 70.
8.See “Removing the LCD Bezel” on page 87.
9.See “Removing the LCD module with the Brackets” on page 88.
10.Release the antenna cables from the aluminium tapes.
11 .Remove the tapes holding the antenna cables in place and release the cables from the latches.. 
StepSize (Quantity)ColorTo r q u e
1~4 M2 x L3 (4) Silver 1.6 kgf-cm 
						

							94Chapter 3
12.Remove the tapes together with the antenna cables from the back cover.  
Removing the Internal Microphone and Web Camera
1.See “Removing the Battery Pack” on page 56.
2.See “Removing the SD dummy card” on page 56. 
						

							Chapter 395
3.See “Removing the ExpressCard dummy card” on page 57.
4.See “Removing the Lower Cover” on page 57.
5.See “Removing the WLAN Board Modules” on page 60.
6.See “Removing the Keyboard” on page 69.
7.See “Removing the LCD Module” on page 70.
8.See “Removing the LCD Bezel” on page 87.
9.See “Removing the LCD module with the Brackets” on page 88.
10.See “Removing the Antennas” on page 93.
11 .Remove the internal microphone from the back cover. 
12.Remove the Web camera from the back cover.  
						

							96Chapter 3 
						

							Chapter 497
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 errors 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 failure 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 99.
POST does not complete. No beep or error 
codes are indicated.“Power-On Self-Test (POST) Error 
Message” on page 102
“Undetermined Problems” on page 116
POST detects an error and displayed 
messages on screen.“Error Message List” on page 103
Other symptoms (i.e. LCD display problems 
or others).“Power-On Self-Test (POST) Error 
Message” on page 102
Symptoms cannot be re-created 
(intermittent problems).Use the customer-reported symptoms and 
go to “Power-On Self-Test (POST) Error 
Message” on page 102
“Intermittent Problems” on page 115
“Undetermined Problems” on page 116
Troubleshooting
Chapter 4 
						

							98Chapter 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 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.
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 cause 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 seated 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:
Numeric keypad 
						

							Chapter 499
External keyboard
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 doagmpstotics 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 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:
“Check the Power Adapter” on page 100
“Check the Battery Pack” on page 101 
						

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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:
Replace the System board.
If the problem is not corrected, see “Undetermined Problems” on page 116.
If 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 101.  Pin 1: +19 to +20.5V
Pin 2: 0V, Ground