Acer TravelMate 4220 TravelMate 4520/4220, Extensa 4420/4120 Service Guide - Page 82

Error Message FRU/Action in Sequence No beep, power indicator turns on, the LCD screen is blank, but you can view POST when connected to an external CRT. Reconnect the LCD-CCD cable. LCD-CCD cable Inverter board LCD panel System board No beep, power indicator turns on and a blinking cursor appears on screen during POST. Ensure every internal cables are properly and securely connected. System board No beep during POST but system runs correctly. Speaker System board POST Beep Codes Code 02h 03h 04h 06h 08h 09h 0Ah 0Bh 0Ch 0Eh 0Fh 10h 11h 12h 13h 14h 16h 17h 18h 1Ah 1Ch 20h 22h 24h 26h 28h 29h 2Ah 2Ch Beeps 1-2-2-3 1-3-1-1 1-3-1-3 1-3-4-1 POST Routine Description Verify Real Mode Disable Non-Maskable Interrupt (NMI) Get CPU type Initialize system hardware Initialize chipset with initial POST values Set IN POST flag Initialize CPU registers Enable CPU cache Initialize caches to initial POST values Initialize I/O component Initialize the local bus IDE Initialize Power Management Load alternate registers with initial POST values Restore CPU control word during warm boot Initialize PCI Bus Mastering devices Initialize keyboard controller BIOS ROM checksum Initialize cache before memory autosize 8254 timer initialization 8237 DMA controller initialization Reset Programmable Interrupt Controller Test DRAM refresh Test 8742 Keyboard Controller Set ES segment register to 4 GB Enable A20 line Autosize DRAM Initialize POST Memory Manager Clear 215 KB base RAM RAM failure on address line xxxx 72 Chapter 4