Acer Aspire 4720z Service Guide
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Chapter 475 Error Message List No beep Error MessagesFRU/Action in Sequence No beep, power-on indicator turns off and LCD is blank.Power source (battery pack and power adapter). See “Power System Check” on page 69.. Ensure every connector is connected tightly and correctly. Reconnect the DIMM. LED board. System board. No beep, power-on indicator turns on and LCD is blank.Power source (battery pack and power adapter). See “Power System Check” on page 69.. Reconnect the LCD connector Hard disk...
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76Chapter 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...
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Chapter 477 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...
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78Chapter 4 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 Multi Processor table 98h 1-2 Search for option ROMs. One long, two short beeps on checksum failure. 99h Check for SMART drive (optional) 9Ah Shadow option ROMs 9Ch Set up Power Management 9Dh...
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Chapter 479 D2h Unknown interrupt CodeBeeps E0h Initialize the chipset E1h Initialize the bridge E2h Initialize the CPU E3h Initialize the system timer E4h Initialize system I/O E5h Check force recovery boot E6h Checksum BIOS ROM E7h Go to BIOS E8h Set Huge Segment E9h Initialize Multi Processor EAh Initialize OEM special code EBh Initialize PIC and DMA ECh Initialize Memory type EDh Initialize Memory size EEh Shadow Boot Block EFh System memory test F0h Initialize interrupt vectors F1h Initialize Run...
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80Chapter 4 Index of Sym ptom-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 Default Settings”, then reboot system. Reconnect the LCD connectors. Keyboard (if contrast and brightness function key doesnt work). LCD inverter ID LCD cable LCD inverter LCD System board Unreadable LCD screen Missing pels in characters Abnormal...
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Chapter 481 Battery can’t be charged See “Check the Battery Pack” on page 71. Battery pack System board PCMCIA-Related Symptoms Symptom / ErrorAction in Sequence System cannot detect the PC Card (PCMCIA) PCMCIA slot assembly System board PCMCIA slot pin is damaged. PCMCIA slot assembly Memory-Related Symptoms Symptom / ErrorAction in Sequence Memory count (size) appears different from actual size.Enter BIOS Setup Utility to execute “Load Default Settings, then reboot system. DIMM System board...
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82Chapter 4 NOTE: If you cannot find a symptom or an error in this list and the problem remains, see “Undetermined Problems” on page 84. 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 System board System hangs intermittently. Reconnect hard disk/CD-ROM drives. Hard disk connection board System board Peripheral-Related Symptoms Symptom / ErrorAction in...
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Chapter 483 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.If any...
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84Chapter 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. NOTE: Verify that the power supply being used at the time of the failure is operating correctly. (See “Power System Check” on...