Acer Travelmate 420 Service Guide

Chapter 373
43.Disconnect the touchpad button board FFC.
44.Release nine locks that secure the touchpad cover.
45.Detach the touchpad cover.
46.Remove the touchpad.
47.Unscrew the four screws holding the antenna line. Two on each side.
48.Remove the antenna line from the upper case.
TM420.book  Page 73  Monday, September 23, 2002  10:27 AM 

74Chapter 3
Disassembling the LCD Module
1.Remove the four screwpad then unscrew the four screws on the LCD bezel. 
2.Detach the LCD bezel from the lower side of the LCD module carefully..
3.Unscrew the screw that holds the LCD inverter.
4.Disconnect the inverter board.
5.Remove the inverter wire.
6.Unscrew the four screws that fasten the LCD to LCD panel. Two on each side.
7.Remove the LCD from the LCD panel.
8.Remove the four (two on each side) screws holding the two LCD brackets then take the brackets...

Chapter 375
Disassembling the External Modules
Disassembling the HDD Module
1.Remove the screw holding the HDD cover. 
2.Take the HDD out of the HDD cover.
3.Remove the four (two on each side) screws on HDD carrier. 
4.Remove the HDD from HDD carrier.
5.Disconnect the HDD connector.
Disassembling the Optical Disk Drive Module/Combo Drive Module
1.Unscrew the two screws holding the ODD cover.
2.Remove another two screws that fasten the ODD cover.
3.Take the ODD assembly out of the ODD cover.
4.Remove the...

76Chapter 3
5.Remove the ODD PCB board.
6.Release the ODD door latch on one side.
7.Then remove the ODD door carefully.
TM420.book  Page 76  Monday, September 23, 2002  10:27 AM 

Chapter 477
Use the following procedure as a guide for computer problems.
NOTE: The diagnostic tests are intended to test this model (TravelMate 420 series).  Non-Acer products, 
prototype cards, or modified options can give false errors and invalid system responses.
1.Obtain the failed 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.If any problem occurs, you can perform visual...

78Chapter 4
System Check Procedures
External Diskette Drive Check
Do the following steps 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. See “System Diagnostic Diskette” on page 52 for details.
1.The FDD heads can become dirty over time,...

Chapter 479
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 main board.
If the keyboard cable connection is correct, run the Keyboard Test. See “System Diagnostic Diskette” on page 
52 for more details.
If the tests detect a keyboard problem, do the following one...

80Chapter 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 main board.
TIf the problem is not corrected, see “Undetermined Problems” on page 90.
TIf the voltage is not correct, go to the next step.
NOTE: An audible noise from the power adapter does not...

Chapter 481
Check the Battery Pack
To check the battery pack, do the following:
From Software:
1.Check out the Power Options in control Panel
2.In Power Meter, confirm that if the parameters shown 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 problem is on recharging or discharging.
From Hardware:
1.Power off the computer. 
2.Remove the battery pack and measure the...

82Chapter 4
still occurs, continue next step.
Replace the CPU with another of the same specifications. If the problems still occurs, go to next 
step.
The main board may be damaged. Replace main board.
3.If the external monitor has the same problem as the internal monitor,  the main board may be damaged. 
Please insert the diagnostic disk and run the display test program and go through the sub-steps under 
step 2.
Sound Check
To determine if the computer’s built-in speakers are functioning properly,...