Acer Travelmate 4720 Service Guide
Have a look at the manual Acer Travelmate 4720 Service Guide online for free. It’s possible to download the document as PDF or print. UserManuals.tech offer 720 Acer manuals and user’s guides for free. Share the user manual or guide on Facebook, Twitter or Google+.
Chapter 4101 * 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 check point code, followed by a delay, the high-order byte, another delay, and then the low-order byte of the error. It repeats this sequence continuously. BIOS Beep Codes for Boot Block in Flash ROM C4h Initialize system error handler C5h PnPnd dual CMOS (optional) C6h Initialize notebook docking (optional) C7h Initialize notebook docking late C8h Force check (optional) C9h Extended checksum (optional) D2h Unknown interrupt CodeBeepsFor Boot Block in Flash ROM 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 Multiprocessor 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 Time Clock F2h Initialize video F3h Initialize System Management Mode F4h 1 Output one beep before boot F5h Boot to Mini DOS F6h Clear Huge Segment F7h Boot to Full DOS CodeBeepsPOST Routine Description
102Chapter 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 TLCD TMainboard Unreadable LCD screen Missing pels in characters Abnormal screen Wrong color displayed TReconnect the LCD connector TLCD inverter ID TLCD cable TLCD inverter TLCD TMainboard LCD has extra horizontal or vertical lines displayed. TLCD inverter ID TLCD inverter TLCD cable TLCD TMainboard Indicator-Related Symptoms Symptom / ErrorCheck or do the following in sequence Indicator incorrectly remains off or on, but system runs correctly TReconnect the inverter board. TMainboard Power-Related Symptoms Symptom / ErrorCheck or do the following in sequence Power shuts down during operation TPower source (battery pack and power adapter). See “Power System Check” on page 93. TBattery pack TPower adapter THard disk drive & battery connection board TMainboard The system doesn’t power-on. TPower source (battery pack and power adapter). See “Power System Check” on page 93. TBattery pack TPower adapter THard disk drive & battery connection board TMainboard
Chapter 4103 The system doesn’t power-off.TPower source (battery pack and power adapter). See “Power System Check” on page 93. THold and press the power switch for more than 4 seconds. TMainboard Battery can’t be charged TSee “Check the Battery Pack” on page 93. 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 Symptoms Symptom / ErrorCheck or do the following in sequence Memory count (size) appears different from actual size. TRun “Load Setup Defaults” in BIOS Setup Utility, then reboot system. TDIMM TMainboard Speaker-Related Symptoms Symptom / ErrorCheck or do the following in sequence In Windows, multimedia programs, no sound comes from the computer. TAudio driver TSpeaker TMainboard Internal speakers make noise or emit no sound. TSpeaker TMainboard Power Management-Related Symptoms Symptom / ErrorCheck or do the following in sequence The system will not enter hibernation TSee “Save to Disk (S4)” on page 44. TKeyboard (if control is from the keyboard) THard disk drive TMainboard The system doesnt enter hibernation mode and four short beeps every minute. TPress Fn+o and see if the computer enters hibernation mode. TTouchpad TKeyboard THard disk connection board THard disk drive TMainboard The system doesn’t enter standby mode after closing the LCD TSee “Save to Disk (S4)” on page 44. TLCD cover switch TMainboard Power-Related Symptoms Symptom / ErrorCheck or do the following in sequence
104Chapter 4 The system doesnt resume from hibernation mode.TSee “Save to Disk (S4)” on page 44. 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 44. TLCD cover switch 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 intermittently. TReconnect hard disk/CD-ROM drives. THard disk connection board TMainboard Peripheral-Related Symptoms Symptom / ErrorCheck or do the following in sequence System configuration does not match the installed devices. TRun “Load Setup Defaults” in BIOS Setup Utility, then reboot system. TReconnect hard disk/CD-ROM/diskette drives. External display does not work correctly. TPress Fn+F5 to switch to LCD or CRT TMainboard USB does not work correctly TMainboard Print problems. TRun printer self-test. TPrinter driver TPrinter cable TPrinter TMainboard Keyboard/Touchpad-Related Symptoms Symptom / ErrorCheck or do the following in sequence Keyboard (one or more keys) does not work. TReconnect the keyboard cable. TKeyboard TMainboard Touchpad does not work. TReconnect touchpad cable. TTouchpad board TMainboard Power Management-Related Symptoms Symptom / ErrorCheck or do the following in sequence
Chapter 4105 NOTE: If you cannot find a symptom or an error in this list and the problem remains, see “Undetermined Problems” on page 107. Modem-Related Symptoms Symptom / ErrorCheck or do the following in sequence Internal modem does not work correctly. TModem phone port TModem combo board TMainboard
106Chapter 4 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 mainboard in loop mode at least 10 times. 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.
Chapter 4107 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. 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 page 93.) Follow procedures below to isolate the failing FRU. Do not isolate non-defective FRU. 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/DVD-ROM drive TPC cards 4.Power on the computer. 5.Determine if the problem has been resolved. 6.If the problem does not recur, reconnect the removed devices one at a time until you find the failed FRU. 7.If the problem persists, replace the following FRU one at a time. Do not replace a non-defective FRU. TSystem board TLCD assembly
Chapter 5109 System Block Diagram System Block Diagram and Connector Locations Chapter 5