Acer Aspire 8942g 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
CN4 PWR/B FFC PU1 Charger IC
U7 LVDS SW IC CN5  Subwoofer, rear, center 
SPK con.
U2 LAN IC PU2 GPU PWR
CN8 KB Backlight conn. PU3 1.5v PWR
CN9 MMB FFC conn. CN6 KB conn.
Y3 14.318MHz CN7 USB
U26 Clock Generator CN10 T/P conn.
CN13 New Card cn Y5 32.768 KHz
U27 1394 & Card IC U21 EC/KBC
CN15 Front SPK conn. U24 BIOS ROM
Y4 32.768KHz PU7 SYS PWR
CN2 LCD, CCD, D-
Microphone conn.CN14 USB FFC
CN3 Logo LED and MMB1 
wire...

208Chapter 5
Bottom View
ItemDescriptionItemDescription
PU8 CUP Core PWR U45 CPU Socket
CN19 Battery conn. CN22 CN23 Mini Card
CN25
1
st HDDJDIM1 & JDIM2 DDR3
CN27 SATA ODD CN30 RTC BAT.
PU11 AXG PWR. U54 NewCard PWR SW
CN34
2
nd HDD conn.PU12 1.05 PWR
U53 PCH (HM55) U57 CIR
CN36 Media Card Reader U50 Center Amp.
U53 CODEC U34 LAN Transformer
CN21 PWM FAN conn. PJ1 DC Jack
CN17 RJ45 CN18 CRT
CN20 DP CN24 HDMI
U43 AMD GPU CN26 eSATA + USB
CN28 USB CN29 IEEE1394
CN31 Line-IN jack CN33 Microphone jack
CN35...

Chapter 5209
Clearing Password Check and BIOS Recovery
This section provides you with standard operating procedures for resetting the BIOS password and BIOS 
recovery for the Aspire 8942. The Aspire 8942 provides one Hardware Open Gap on the 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...

210Chapter 5
7.Plug in AC, keeping the HW Gap shorted, and press Power Button to power on the system till BIOS POST 
is finished. Once BIOS POST has run, remove the tool from the HW Gap.
8.Restart the system. Press the F2 key to enter BIOS Setup menu.
If there is no Password request, the BIOS Password has been successfully cleared. Otherwise, follow the 
steps and try again.
BIOS Recovery by Crisis Disk
BIOS Recovery Boot Block:
The BIOS Recovery Boot Block is a special block of BIOS which is used to...