Acer Travelmate 720 Service Guide

Chapter 4 93
Keyboard (one or more keys) 
does not work.1.  Reseat the keyboard cable.
2.  Keyboard
3.  System board
Power shuts down during 
operation.1.  Battery
2.  AC Adapter
3.  DC/DC & Charge board
4.  System board
The system will not power-
on.1.  Battery
2.  AC adapter
3.  DC/DC & Charge boar
4.  System board
The system will not power-
off.1.  DC/DC & Charge board
2.  System board
Battery can’t be charged. 1.  Battery
2.  DC/DC & Charge board
3.  IDE board
4.  System board
System cannot detect...

94 Troubleshooting
In DOS or Windows 
multimedia programs, no 
sound comes from the 
computer. 1.  Speaker
2.  System board
External display does not 
work correctly.System board
USB does not work correctly. System board
Print problems 1.  Run printer self-test.
2.  Printer driver
3.  Printer cable
4.  System board
Serial or parallel port device 
problems1.  Device driver
2.  Device cable
3.  Device
4.  System board
Symptom / ErrorFRU / Action in Sequence
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Chapter 4 95
Intermittent Problems
Intermittent system hang problems can be caused by a variety of reasons 
that have nothing to do with a hardware defect, such as: cosmic radiation, 
electrostatic discharge, or software errors. FRU replacement should be 
considered only when a recurring problem exists.
When analyzing an intermittent problem, do the following:
1.  Run the advanced diagnostic test for the System board in loop mode at 
least 10 times.
2.  If no error is detected, do not replace any FRU.
3....

96 Troubleshooting
Undetermined Problems
You are here because the diagnostic tests did not identify which adapter or 
device failed, installed devices are incorrect, a short circuit is suspected, or 
the system is inoperative. Follow these procedures to isolate the failing FRU 
(do not isolate a nondefective FRU).
Note: 
Verify that all attached devices are supported by the computer.
Note: 
Verify that the power supply being used at the time of the failure is 
operating correctly (See “Power Systems...

Chapter 4 97
Utility Program Diskette
Setting LCD Panel ID
There is an EEPROM in the inverter which stores its supported LCD type ID 
code. If you replace an LCD with one of a different brand or use a new 
inverter, the ID information in the inverter EEPROM should be updated.
Follow the steps below to see the LCD Panel ID:
1.  Follow the instructions on-screen to read current or to set new LCD Panel 
ID code.
Note: 
When you set a new LCD Panel ID and the new LCD is not yet 
enabled (to function),...

98 Troubleshooting
Running the Diagnostics
Running PQA Diagnostics Program
Note: 
Before running the PQA Diagnostics Program, make sure that the 
write enable tab of the Diagnostic Program Diskette is set to 
enabled.
Press -> or 

Chapter 4 99
Auto Test performs multiple tests of the selected items and automatically 
checks the selected test items in sequence.
Note:  PCMCIA Diagnostic Supports the Manual test only. Do not select 
 PCMCIA Diagnostic in Auto Test.
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100 Troubleshooting
The screen below appears if you select AUTO Test.
Specify the desired number of tests and press Enter. After you specify the 
number of tests to perform, the screen shows a list of test items (see below):
. 
Move the highlight bar from one item to another. Press space to enable or 
disable the item. Press Enter to view the available suboptions of each 
selected item. Press Esc to close the submenu.
The right corner screen information gives you the available function keys and 
the...

Chapter 4 101
PQA Diagnostics Program Error Codes and Messages
Error CodeMessageFRU/Action in Sequence
System
16XX Backup battery error Backup battery
1XXX CPU or System board 
error1.  Reload BIOS default setting.
2.  CPU
3.  System board
2XXX Memory error 1.  Reseat CPU (IMM module).
2.  DIMM
3.  System board
3XXX Keyboard error 1.  Reseat Keyboard.
2.  Keyboard
3.  System board
4XXX Video error System board
5XXX Parallel Port error System board
6XXX Serial port or System 
board errorSystem board
7XXX...

102 Troubleshooting
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