Acer Aspire 7720 Service Guide

							Chapter 365
NOTE: RF board on selected models only.
11 .Remove the four screws fastening the ODD board to the lower case.
12.Remove the ODD board from the lower case.
13.Remove the two screws fastening the audio board to the lower case.
14.Disconnect the audio board cable from the motherboard.
15.Disconnect the subwoofer cable from the audio board.
16.Remove the audio board from the lower case unit.
17.Remove the screw fastening the main board to the lower case.
18.Detach the main board from the lower case as shown.
19.Turn the main board over, then remove the DC-in connector from the board as shown. 
						

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20.Remove the three screws fastening the subwoofer to the lower case.
21.Remove the subwoofer from the lower case as shown. 
						

							Chapter 367
Disassembling the Upper Case Assembly
1.Turn the upper case over.
2.Remove the two screws fastening the button board.
3.Detach the button board with FFC from the upper case as shown.
4.Remove the two screws fastening the LED board.
5.Detach the LED board with FFC from the upper case as shown.
6.Remove the four screws fastening the speakers.
7.Remove the speakers from the upper case as shown. 
						

							68Chapter 3
Disassembling the LCD Module
1.Remove the four screw rubbers as shown.
2.Then remove the four screws fastening the LCD bezel.
3.Detach the LCD bezel from the LCD module carefully.
4.Remove the two screws holding the LCD and the one screw holding the inverter board to the LCD panel.
5.Detach the two inverter cable connectors from the inverter board.
6.Detach the CCD cable connector from the CCD board.
7.Remove the two screws fastening the CCD module to the LCD panel and remove the CCD module.
8.Remove the two screws fastening the CCD board to the CCD bracket.
9.Lift out the LCD from the LCD panel as shown. 
						

							Chapter 369
10.Remove the four screws fastening the left LCD bracket and detach it.
11 .Remove the four screws fastening the right LCD bracket and detach it.
12.Disconnect the LCD cable from the rear side of the LCD. 
						

							70Chapter 3
Disassembling the External Modules
Disassembling the HDD Module
1.Turn over the HDD module and remove the three screws fastening the HDD board.
2.Remove the HDD board.
3.Turn over the HDD module and remove the eight screws fastening the HDD bracket.
4.Remove the 
Disassembling the ODD Module
1.Remove the three screws holding the optical bracket.
2.Then remove the optical bracket from the optical disk drive. 
						

							Chapter 471
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 73
POST does not complete. No beep or error 
codes are indicated.“Power-On Self-Test (POST) Error Message” on 
page 76
“Undetermined Problems” on page 88
POST detects an error and displayed messages 
on screen.“Error Message List” on page 77
Other symptoms (i.e. LCD display problems or 
others).“Power-On Self-Test (POST) Error Message” on 
page 76
Symptoms cannot be re-created (intermittent 
problems).Use the customer-reported symptoms and go to 
“Power-On Self-Test (POST) Error Message” on 
page 76
“Intermittent Problems” on page 87
“Undetermined Problems” on page 88
Troubleshooting
Chapter 4 
						

							72Chapter 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:
TNumeric keypad
TExternal keyboard 
						

							Chapter 473
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:
T“Check the Power Adapter” on page 74
T“Check the Battery Pack” on page 75 
						

							74Chapter 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, see “Undetermined Problems” on page 88.
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 75. 
Pin 1: +19 to +20.5V
Pin 2: 0V, Ground