Acer Aspire 8920g Service Guide

							Chapter 371
Disassembling the Main Unit
1. Turn over the keyboard as the image shows.
2.Disconnect the Keyboard FFC from the main board
3.Then remove the keyboard from the main unit.
4.Disconnect the FFC from the main board.
5.Loose One screws from the TPCB.
6.Disconnect the LCM cable.
7.Pull out the Power cable.
8.Pull out the Wireless antenna.
9.Release four TPCB locker then remove the TCB from machine.
Disassembling the LED boards
10.Loose the LED boards four screws.
11 .Remove two LED boards from the machine. 
						

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12.Loose four LCM hinge screws.
13.Then remove LCM module from the machine.
Remove I/O baord and Main Board.
14.Remove the daughter board from the machine. 
						

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15.Loose two Modem card screws.
16.Disconnect Modem card cable.
17.Remove Modem card from the M/B.
18.Disconnect Speaker cable from the MB and loose the MB screw.
19.Remove M/B from the BTCB.
20.Remove RJ11 from the BTCB. 
						

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21.Remove the USB board from BTCB..
Disassembly LCM module
1.Remove six LCM bezel mylar.
2.Loose 10 LCM bezel screws.
3.Remove LCM bezel.
4.Disconnect Inverter cable and Back LED board cable.
5.Remove Inverter from BTCB..
6.Loose four LCD scrws from the hinge.
7.Disconnect CCD cable.
8.Remove the LCD panel. 
						

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9.Loose four LCD hinge screws, then remove two hinges from LCD panel. 
						

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Disassembling the External Modules
Disassembling the HDD Module
1.Remove the four screws holding the HDD (hard disk drive) foil; two on each side.
2.Carefully take out the hard disk drive from the HDD foil.
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 479
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 81.
POST does not complete. No beep or error 
codes are indicated.“Power-On Self-Test (POST) Error Message” on 
page 84
“Undetermined Problems” on page 96
POST detects an error and displayed messages 
on screen.“Error Message List” on page 85
Other symptoms (i.e. LCD display problems or 
others).“Power-On Self-Test (POST) Error Message” on 
page 84
Symptoms cannot be re-created (intermittent 
problems).Use the customer-reported symptoms and go to 
“Power-On Self-Test (POST) Error Message” on 
page 84
“Intermittent Problems” on page 95
“Undetermined Problems” on page 96
Troubleshooting
Chapter 4 
						

							80Chapter 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:
qNumeric keypad
qExternal 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 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 82
                  “Check the Battery Pack” on page 83 
						

							82Chapter 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:
                   Replace the System board.
                   If the problem is not corrected, see “Undetermined Problems” on page 96.
                   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 83. 
Pin 1: +19 to +20.5V
Pin 2: 0V, Ground