Acer Aspire 4715z Service Guide

Chapter 491
Power-On Self-Test (POST) Error Message 
The POST error message index lists the error message and their possible causes. 
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.
The error messages are listed in the coming pages to indicate the BIOS signals on the screen and the error 
symptoms classified by functions. If the...

92Chapter 4
Index of Error Messages
Error Message List
Error MessagesCheck or do the following in sequence:
Stuck Key See “Keyboard or Auxiliary Input Device Check” on page 88. 
System CMOS checksum bad - Default 
configuration used
TRTC battery.
TRun the BIOS Setup Utility to reconfigure the system time, 
then reboot system.
Real time clock error
TRTC battery
TRun the BIOS Setup Utility to reconfigure system time, then 
reboot system.
TMainboard
Previous boot incomplete - Default 
configuration used...

Chapter 493
No beep, power-on indicator turns off and 
LCD is blank.TPower source (battery pack and power adapter). See “Power 
System Check” on page 89.
TEnsure every connector is connected tightly and correctly. 
TReconnect the DIMM.
TLED board
TMainboard
No beep, power-on indicator turns on and 
LCD is blank.
TPower source (battery pack and power adapter). See “Power 
System Check” on page 89.
TReconnect the LCD connector
THard disk drive
TLCD inverter ID
TLCD cable
TLCD Inverter board
TLCD...

94Chapter 4
Phoenix BIOS Beep Codes
CodeBeepsPOST Routine Description
02h Verify Real Mode
03h Disable Non-Maskable Interrupt (NMI)
04h Get CPU type
06h Initialize system hardware
08h Initialize chipset with initial POST values
09h Set IN POST flag
0Ah Initialize CPU registers
0Bh Enable CPU cache
0Ch Initialize caches to initial POST values
0Eh Initialize I/O component
0Fh Initialize the local bus IDE
10h Initialize Power Management
11h Load alternate registers with initial POST values
12h Restore CPU...

Chapter 495
46h 2-1-2-3 Check ROM copyright notice
48h Check video configuration against CMOS
49h Initialize PCI bus and devices
4Ah Initialize all video adapters in system
4Bh QuietBoot start (optional)
4Ch Shadow video BIOS ROM
4Eh Display BIOS copyright notice
50h Display CPU type and speed
51h Initialize EISA board
52h Test keyboard
54h Set key click if enabled
58h 2-2-3-1 Test for unexpected interrupts
59h Initialize POST display service
5Ah Display prompt “Press F2 to enter SETUP”
5Bh Disable CPU...

96Chapter 4
8Ah Initialize Extended BIOS Data Area
8Bh Test and initialize PS/2 mouse
8Ch Initialize floppy controller
8Fh Determine number of ATA drives (optional)
90h Initialize hard-disk controllers
91h Initialize local-bus hard-disk controllers
92h Jump to UserPatch2
93h Build MPTABLE for multi-processor boards
95h Install CD-ROM for boot
96h Clear huge ES segment register
97h Fixup Multiprocessor table
98h 1-2 Search for option ROMs. One long, two short beeps on checksum 
failure.
99h Check for...

Chapter 497
*  If the BIOS detects error 2C, 2E, or 3O (base 512K RAM error), it displays an additional word-bitmap (xxxx) indicating 
the address line or bits that failed. For example, 2C 0002 means address line 1 (bit one set) has failed. 2E 1020 
means data bits 12 and 5 (bits 12 and 5 set) have failed in the lower 16 bits. Note that error 30 cannot occur on 386SX 
systems because they have a 16 rather than 32-bit bus. The BIOS also sends the bitmap to the port-80 LED display. It 
first displays the...

98Chapter 4
Index of Symptom-to-FRU Error Message
LCD-Related Symptoms
Symptom / ErrorCheck or do the following in sequence
LCD backlight doesnt work
LCD is too dark
LCD brightness cannot be adjusted
LCD contrast cannot be adjusted
TRun “Load Setup Defaults” in BIOS Setup Utility, then reboot 
system.
TReconnect the LCD connectors.
TKeyboard (if contrast and brightness function key doesnt 
work).
TLCD inverter ID
TLCD cable
TLCD inverter board
TLCD
TMainboard
Unreadable LCD screen 
Missing pels in...

Chapter 499
The system doesn’t power-off.TPower source (battery pack and power adapter). See “Power 
System Check” on page 89. 
THold and press the power switch for more than 4 seconds.  
TMainboard
Battery can’t be charged
TSee “Check the Battery Pack” on page 89. 
TBattery pack
TMainboard
PCMCIA-Related Symptoms
Symptom / ErrorCheck or do the following in sequence
System cannot detect the PC Card 
(PCMCIA) 
TPCMCIA slot assembly
TMainboard
PCMCIA slot pin is damaged. PCMCIA slot assembly
Memory-Related...

100Chapter 4
The system doesnt resume from 
hibernation mode.TSee “Save to Disk (S4) on page 34.
THard disk connection board
THard disk drive
TMainboard
The system doesnt resume from standby 
mode after opening the LCD.
TSee “Save to Disk (S4) on page 34.
TMainboard
Battery fuel gauge in Windows doesn’t go 
higher than 90%. 
TRemove battery pack and let it cool for 2 hours.
TRefresh battery (continue use battery until power off, then 
charge battery).
TBattery pack
TMainboard
System hangs...