Acer Aspire 2020 Service Guide

							Chapter 474
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 voltage between battery terminals 1(+) and 6(ground).
3.If the voltage is still less than 7.5 Vdc after recharging, replace the battery.
4.If the voltage is within the normal range, run the diagnostic program.
To check the battery charge operation, use a discharged battery pack or a battery pack that has less than 50% 
of the total power remaining when installed in the computer. 
If the battery status indicator does not light up, remove the battery pack and let it return to room temperature. 
Re-install the battery pack.
If the charge indicator still does not emit, replace the battery pack. If the charge indicator still does not light up, 
replace the DC/DC charger board.
Touchpad Check
If the touchpad doesn’t work, do the following actions one at a time to correct the problem. Do not replace a 
non-defective FRU:
1.After rebooting, run Touch pad/PS2 Mode Driver.
2.Run utility with the PS/2 mouse function and check if the mouse is working.
3.If the PS/2 mouse does not work, then check if the main board to switch board FPC is connected well.
4.If the main board to switch board FPC is connected well, then check if the touch pad  FPC connects to the 
main board properly.
5.If there is still an error after you have connected the touch pad FPC to the main board properly, then 
replace the touch pad or touch pad FPC. The touch pad or touch pad FPC may be damaged.
6.Replace switch board.
7.If the touch pad still does not work, then replace the FPC on Track Pad PCB.
After you use the touchpad, the pointer drifts on the screen for a short time. This self-acting pointer movement 
can occur when a slight, steady pressure is applied to the touchpad pointer. This symptom is not a hardware 
problem. No service actions are necessary if the pointer movement stops in a short period of time.
Display Check
1.Connect an external display to the computer’s external monitor port, the boot the computer. The computer 
can automatically detect the external display. Press Fn+ p to switch to the external display.
2.If the external display works fine, the internal LCD may be damaged. Then perform the following steps:
Make sure the DDRRAM module is seated properly. Then run the diplay test again. If the problem 
still exists, go to next step.
Replace the inverter board, then run the display test program again. If the problem still occurs, go 
on next step.
Replace the LCD module with a new one then run the display test again. If the probelm still 
happens, continue next step.
Replace LCD/FL cable with a new one then execute the display diagnostic again. If the problem  
						

							75Chapter 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, perform the following steps. Before 
you start the steps below, adjust the speaker volume to an appropriate level. 
1.Try different audio sources. For example, employ audio CD and ditital music file to determine whether the 
fault is in the speaker system or not. If not all sources have sound problem, the problem is in the source 
devices. If all have the same problem, continue next step.
2.Connect a set of earphone or external speakers. If these devices work fine, go to next step. If not, then the 
main board may be defective or damaged. Replace the main board.
3.Follow the disassembling steps in Chapter 3. Esure the speaker cable is firmly connected to the main 
board. If the speaker is still a malfunction, go on next step.
4.If the speakers do not sound properly, the speakers may be defective or damaged. Replace the speakers. 
If the problem still occurs, then replace the main board. 
						

							Chapter 476
Insyde MobilePro BIOS POST Beep Code and POST Messages
The POST error message index lists the error message and their possible causes. The most likely cause is 
listed first.
NOTE: Perform the FRU replacement or actions in the sequence shown in FRU/Action column, if the FRU 
replacement does not solve the problem, put the original part back in the computer. Do not replace a 
non-defective FRU.
This index can also help you determine the next possible FRU to be replaced when servicing a computer.
If the symptom is not listed, see “Undetermined Problems” on page 73.
The following lists the error messages that the BIOS displays on the screen and the error symptoms classified 
by function. 
NOTE: Most of the error messages occur during POST. Some of them display information about a hardware 
device, e.g., the amount of memory installed. Others may indicate a problem with a device, such as the 
way it has been configured.
NOTE: If the system fails after you make changes in the BIOS Setup Utility menus, reset the computer, enter 
Setup and install Setup defaults or correct the error.
Beep CodeMessageDescription
short, short, short; short, 
short, long“FAULTY DMA PAGE 
REGISTERS”DMA page registers do not function 
properly.
short, short, short; short, 
long, short“FAULTY REFRESH CIRCUIT” RAM refresh circuit does not function 
properly.
short, short, short; short, 
long, long“ROM CHECKSUM INCORRECT” BIOS ROM checksum failed.
short, short, short; long, 
short, short“CMOS RAM TEST FAILED” CMOS RAM test failed.
short, short, short; long, 
short, long“DMA CONTROLLER FAULTY” DMA controller does not work properly.
short, short, short; long, 
long short“INTERRUPT CONTROLLER 
FA I L E D ”The interrupt controller does not work 
properly.
short, short, short; long, 
long, longN/A
Keyboard controller failed to respond with 
the self-test command.
short, short, long; short, 
short, shortN/A No video device found.
short, short, long; short, 
short, longN/A No RAM installed.
N/A “KEYBOARD CONTROLLER 
FA I L U R E ”Keyboard controller failed during system 
inquiry about connected devices.
N/A “KEYBOARD FAILURE”
The keyboard fails to respond or no key-
board is connected.
N/A “CMOS FAILURE - RUN SCU”
CMOS data error, probably due to battery 
power loss.
N/A “CMOS CHECKSUM INVALID - 
RUN SCU”CMOS checksum error.
N/A
“RAM ERROR AT LOCATION 
xxxxxx:
WROTE: xxxx
READ: xxxx”The RAM failed during memory test at the 
indicated location. 
						

							77Chapter 4
N/A
“PARITY ERROR AT UNKNOWN
LOCATION”Parity error during memory test at unknown 
location.
N/A “PARITY ERROR AT LOCATION 
XXXXXX”Parity error during memory test at the 
indicated location.
N/A “NO INTERRUPTS FROM TIMER 
0”Timer 0 of the clock timer controller does 
not generate system interrupts correctly.
N/A “UNEXPECTED AMOUNT OF 
MEMORY - RUN SCU”The system memory size does not match 
with the CMOS record.
N/A “CLOCK NOT TICKING 
CORRECTLY”The system clock does not working 
correctly.
N/A “TIME/DATA CORRUPT - RUN 
SCU”The time/date information in CMOS is 
invalid.
N/A “MACHINE IS LOCKED - TURN 
KEY”The keyboard operation is locked.
N/A “BOOT SECTOR 0 HAS 
CHANGED”The boot sector of the hard disk has been 
changed, probably because of a virus 
attack.
N/A Suspend-to-Disk partition 
MISSING!”No Suspend-to-Disk partition found.
N/A “Hard Disk ERROR!” Access to the Suspend-to-Disk partition 
failed.
N/A “Suspend-to-Disk partition 
signature NOT FOUND!”No Suspend-to-Disk partition signature 
found.
N/A “Suspend-to-Disk partition size 
TOO SMALL!”The capacity of the Suspend-to-Disk 
partition is not enough.
N/A “MEMORY SIZE HAS CHANGED 
-- REBOOTING”The memory size has changed after 
previous Suspend-to-Disk operation.
Beep CodeMessageDescription 
						

							Chapter 478
Index of Symptom-to-FRU Error Message
LCD-Related Symptoms
Symptom / ErrorAction in Sequence
LCD backlight doesnt work
LCD is too dark
LCD brightness cannot be adjusted
LCD contrast cannot be adjustedEnter BIOS Utility to execute “Load Setup Defaults” on Exit 
screen, then reboot system.
Reconnect the LCD connectors.
Keyboard (if contrast and brightness function key doesnt 
work).
LCD cable
LCD inverter
LCD
Main board
Unreadable LCD screen 
Missing pels in characters
Abnormal screen 
Wrong color displayedReconnect the LCD connector
LCD cable
LCD inverter
LCD
Main board
LCD has extra horizontal or vertical lines 
displayed.LCD inverter
LCD cable
LCD
Main board
Indicator-Related Symptoms
Symptom / ErrorAction in Sequence
Indicator incorrectly remains off or on, but 
system runs correctlyReconnect the inverter board
Inverter board
Main board
Power-Related Symptoms
Symptom / ErrorAction in Sequence
Power shuts down during operation Power source (battery pack and power adapter). See “Power 
System Check” . 
Battery pack
Power adapter
Hard drive & battery connection board
Main board
The system doesn’t power-on. Power source (battery pack and power adapter). See “Power 
System Check” .
Battery pack
Power adapter
Hard drive & battery connection board
Main board
The system doesn’t power-off. Power source (battery pack and power adapter). See “Power 
System Check” . 
Hold and press the power switch for more than 4 seconds.  
Main board
Battery can’t be charged See “Check the Power Adapter”.
Battery pack
Main board 
						

							79Chapter 4
PCMCIA-Related Symptoms
Symptom / ErrorAction in Sequence
System cannot detect the PC Card 
(PCMCIA) PCMCIA slot assembly
Main board
PCMCIA slot pin is damaged. PCMCIA slot assembly
Memory-Related Symptoms
Symptom / ErrorAction in Sequence
Memory count (size) appears different from 
actual size.DIMM
Main board
Speaker-Related Symptoms
Symptom / ErrorAction in Sequence
In Windows, multimedia programs, no 
sound comes from the computer. See “Sound Check” on page 66
Audio driver
Speaker
Main board
Internal speakers make noise or emit no 
sound.See “Sound Check” on page 66
Speaker
Main board
Power Management-Related Symptoms
Symptom / ErrorAction in Sequence
The system will not enter hibernation Keyboard (if control is from the keyboard)
Hard disk drive
Main board
The system doesnt enter hibernation mode 
and four short beeps every minute.Press Fn+F4 and see if the computer enters hibernation 
mode.
Touchpad
Keyboard
Hard disk connection board
Hard disk drive
Main board
The system doesn’t enter standby mode 
after closing the LCDLCD cover switch
Main board
The system doesnt resume from 
hibernation mode.Hard disk connection board
Hard disk drive
Main board
The system doesnt resume from standby 
mode after opening the LCD.LCD cover switch
Main board
Battery fuel gauge in Windows doesn’t go 
higher than 90%. Remove battery pack and let it cool for 2 hours.
Refresh battery (continue use battery until power off, then 
charge battery).
Battery pack
Main board 
						

							Chapter 480
System hangs intermittently. Reconnect hard disk drives. 
Hard disk drive connector
Main board
Peripheral-Related Symptoms
Symptom / ErrorAction in Sequence
System configuration does not match the 
installed devices. Enter BIOS Setup Utility to execute “Load Setup defaults”, 
then reboot system.
Reconnect hard disk/CD-ROM/diskette drives.
External display does not work correctly. See if there is an error beep. If there is an erro beep, then 
change main board.
Power off. Then check if RAM CPU BIOS are well-
connected.
Press Fn+F5 three times slowly
LCD FPC
LCD inverter
LCD
USB does not work correctly USB device cable is firmly connected into the USB ports. 
Test one USB port each time.
USB socket is firmly secured to the main board.
Main board
Print problems. Ensure the “Parallel Port” in the “System Devices” of BIOS 
Setup Utility is set to Enabled.
Onboard Devices Configuration
Run parallel port test
Printer driver
Printer cable
Printer
Main board
Keyboard/Touchpad-Related Symptoms
Symptom / ErrorAction in Sequence
Keyboard (one or more keys) does not 
work.Reconnect the keyboard cable.
Keyboard
Main board
Touchpad does not work. Reconnect touch pad cable. Modem port is secured to the 
main board
Touch pad FPC
Audio/Touch pad board
Main board Power Management-Related Symptoms
Symptom / ErrorAction in Sequence 
						

							81Chapter 4
Modem-Related Symptoms
Symptom / ErrorAction in Sequence
Internal modem does not work correctly. Ensure the telephone cable is firmly plugged into the 
telephone wall socket and the modem port of the computer.
Modem phone port is secured to the main board.
modem combo board
Main board 
						

							Chapter 482
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 diagnostic test for several times to isolate the problem.
2.If no error is detected, do not replace any FRU.
3.If any error is detected, replace the FRU.  Rerun the test to verify that there are no more errors. 
						

							83Chapter 4
Undetermined Problems
The diagnostic problems does not identify which adapter or device failed, which installed devices are incorrect, 
whether a short circuit is suspected, or whether the system is inoperative.  
Follow these procedures to isolate the failing FRU (do not isolate non-defective FRU).
NOTE: Verify that all attached devices are supported by the computer.
1.Power-off the computer.
2.Visually check them for damage. If any problems are found, replace the FRU.
3.Remove or disconnect all of the following devices:
TNon-Acer devices
TPrinter, mouse, and other external devices
TBattery pack
THard disk drive
TDIMM 
TCD-ROM/Diskette drive Module
TPC Cards
4.Power-on the computer.
5.Determine if the problem has changed.
6.If the problem does not recur, reconnect the removed devices one at a time until you find the failing FRU.
7.If the problem remains, replace the following FRU one at a time. Do not replace a non-defective FRU:
TMain board
TLCD assembly