Acer Aspire 8940 Service Guide

Chapter 4201
USB (Right Up/Down Side) Failure
If the right-side USB fails, perform the following actions one at a time to correct the problem. Do not replace 
non-defective FRUs:
Other Failures
If the CRT Switch, Dock, LAN Port, external MIC or Speakers, PCI Express Card, 5-in-1 Card Reader or 
Volume Wheel fail, perform the following general steps to correct the problem. Do not replace non-defective 
FRUs:
1.Check Drive whether is OK.
2.Check Test Fixture is ok.
3.Swap M/B to Try.
Intermittent Problems...

202Chapter 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 On 
Issue” on...

Chapter 4203
Post Codes
These tables describe the POST codes and descriptions during the POST.
Chipset POST Codes
The following table details the chipset POST codes and functions used in the POST.
Code Beeps POST 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...

204Chapter 4
3Ah Autosize cache 
3Ch  Advanced configuration of chipset registers 
3Dh Load alternate registers with CMOS values 
42h Initialize interrupt vectors 
45h POST device initialization 
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...

Chapter 4205
86h  Re-initialize onboard I/O ports. 
87h  Configure Motherboard Configurable Devices (optional) 
88h  Initialize BIOS Data Area 
89h  Enable Non-Maskable Interrupts (NMIs) 
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...

206Chapter 4
* If the BIOS detects error 2C, 2E, or 30 (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...

Chapter 5207
Jumper and Connector Locations
Top View
ItemDescriptionItemDescription
U6 PWR/B FFC connector PU2 Charger IC
U18 Second thermal IC CN9 Subwoofer, rear, 
center SPK connector
U9 LAN IC CN11 KB connector
CN4 KB Backlight 
connectorCN12 T/P connector
CN1 MMB2 FFC connector U23 BIOS ROM
U15 Clock Generator CN15 USB
Y2 14.318MHz CN13 MMB & VR
CN3 New Card connector U24 EC/ KBC
U14 1394 & Card IC Y5 32.768KHz
CN2 Front SPK connector U22 ID ROM
Y4 32.768KHz PU3 RAM PWR
CN5 LCD, CCD, D-
microphone...

208Chapter 5
Bottom View
ItemDescriptionItemDescription
U28 CPU socket  CN28 RJ45
PU5 CPU Core PWR  CN30 CRT
CN21 Battery conn.  CN36 DP 
PU6 Render Standby  CN27 HDMI
CN37 CN38  Mini Card CN25 MXM-3 
CN20 First HDD CN31 eSATA + USB
CN22 CN23 DDR3 CN CN32 USB 
CN18 SATA ODD  CN35 IEEE1394 
U27 First  Thermal IC CN33 Line-IN jack 
U29 GMCH (NB) CN34 Microphone jack 
U39 New Card PWR SW CN29 Phone jack & S/PDIF 
CN17 Second  HDD conn.  U44 Subwoofer Amp. 
PU7 3 & 5V PWR  U35 Rear & HP Amp. 
U31 ICH9 (SB)...

Chapter 5209
Clearing Password Check and BIOS Recovery
This section provide you the standard operating procedures of clearing password and BIOS recovery for 
Aspire 8940. Aspire 8940 provides one Hardware Open Gap on main board for clearing password check, and 
one Hotkey for enabling BIOS Recovery.
Clearing Password Check
Hardware Open Gap Description is as follows:
If users set a BIOS Password (Supervisor Password and/or User Password) for security reasons, the BIOS will 
prompt for a password during...

210Chapter 5
7.Plug in AC, keeping the HW Gap shorted, and press Power Button to power on the system till BIOS POST 
finish. Then remove the tool from the HW Gap.
8.Restart system. Press F2 key to enter BIOS Setup menu.
If there is no Password request, the BIOS Password has been successfully cleared. Otherwise, please follow 
the steps and try again.
NOTE: The steps are only for clearing BIOS Password (Supervisor Password and User Password).
BIOS Recovery by Crisis Disk
BIOS Recovery Boot Block:
BIOS...