Acer Aspire 7420 Service Guide

							Chapter 373
Main Unit Disassembly Process
Main Unit Disassembly Flowchart
Removing the Modem Board 
1.See “Removing the Battery Pack” on page 62.
2.See “Removing the Lower Cover” on page 64. Screw List
ScrewPart No.
A M2.5 x L6 86.00E33.736
C M2 x L4 86.9A552.4R0
D M2.5 x L5 86.00E74.335
H M2.5 x L8 86.00E34.738
J M2 x L4 86.00F24.724
MAIN UNIT
KEYBOARD
MAIN
BOARD Cx4
MAIN UNIT DISASSEMBLY
MIDDLE
COVER
LCD MODULE
Hx2 Ax 2
UPPER CASE
Ax 20
LEFT AND RIGHT
SPEAKER MODULE
Cx4
MODEM
BOARD Cx2 Cx2
CPU/VGA
THERMAL MODULE
CPU
TOUCH PAD BRACKET
ASSEMBLY
Cx4
TOUCH PAD
BRACKET
LAUNCH BOARD
Jx1 HEAT SINK FAN
USB BOARD
C x9 (Cx5 for UMA module)
VGA
BOARD
POWER
BOARD
Cx 1
Dx2
TOUCH PAD
BOARDFINGERPRINT
BOARD
Cx1
ODD BOARD 
						

							74Chapter 3
3.See “Removing the DIMM” on page 68.
4.See “Removing the WLAN Board Modules” on page 68.
5.Remove the 2 screws (C) securing the modem card. 
6.Lift partially to detach the modem board from the main board. 
NOTE: The modem cable is still attached to the modem board.
7.Disconnect the modem cable from the modem board. 
Removing the Heatsink Fan Module
1.See “Removing the Battery Pack” on page 62.
2.See “Removing the Lower Cover” on page 64.
StepSize (Quantity)ColorTo r q u e
1~2 M2 x L4 (2) Silver 1.8 kgf-cm 
						

							Chapter 375
3.Disconnect the heatsink fan connector from FAN1 on the main board. 
4.Remove the two screws (C) securing the heatsink fan module.   
5.Remove the heatsink fan module from the main board. 
Removing the CPU and VGA Heatsink Module
1.See “Removing the Battery Pack” on page 62.
2.See “Removing the Lower Cover” on page 64.
StepSize (Quantity)ColorTo r q u e
1~2 M2 x L4 (2) Silver 1.6 kgf-cm 
						

							76Chapter 3
3.Remove the nine screws (C) securing the CPU and VGA heatsink module in place.   
4.Slide out and remove the heatsink module. 
Removing the CPU 
1.See “Removing the Battery Pack” on page 62..
2.See “Removing the Lower Cover” on page 64..
3.See “Removing the Heatsink Fan Module” on page 74.
4.See “Removing the CPU and VGA Heatsink Module” on page 75.
StepSize (Quantity)ColorTo r q u e
1~9 M2 x L4 (9) Silver 3.0 kgf-cm 
						

							Chapter 377
5.Using a flat screwdriver, turn the CPU socket latch counter-clockwise to release the CPU, then remove 
the CPU. 
NOTE: When installing the CPU, make sure to install the CPU with PIN 1 at the corner as shown. 
Removing the VGA board (for Discrete model only)
1.See “Removing the Battery Pack” on page 62.
2.See “Removing the Lower Cover” on page 64.
3.See “Removing the Heatsink Fan Module” on page 74.
4.See “Removing the CPU and VGA Heatsink Module” on page 75.
5.Remove the two screws (D) securing the VGA board.  
StepSize (Quantity)ColorTo r q u e
1~2 M2.5 x L5 (2) Silver 1.6 kgf-cm 
						

							78Chapter 3
6.Carefully remove the VGA board from the main board. 
Removing the Middle Cover and the Power Board
1.See “Removing the Battery Pack” on page 62.
2.Open the LCD screen all the way to facilitate the easy removal of the middle cover. 
3.To remove the Middle Cover, carefully insert the plastic flat screwdriver under the side of the middle cover 
and gently pry up the middle cover. Continue prying on the other side until you could detach the Middle 
Cover.  
4.Detach the cover and turn it over on the keyboard.   
						

							Chapter 379
5.Disconnect the Power board cable from the main board and disconnect the Power board cable. 
6.Remove the one screw (C) securing the Power board to the middle cover, and remove the Power board 
from the middle cover.   
Removing the Keyboard
1.See “Removing the Battery Pack” on page 62..
2.See “Removing the Middle Cover and the Power Board” on page 78.
StepSize (Quantity)ColorTo r q u e
1 M2 x L4 (1) Silver 1.6 kgf-cm 
						

							80Chapter 3
3.Release the top latches securing the keyboard in place.
4.Carefully pry the keyboard out of the side latches and slide it out; then turn it over on the touchpad area.  
5.Disconnect the keyboard cable from the main board to remove the keyboard.    
						

							Chapter 381
Removing the LCD Module
1.See “Removing the Battery Pack” on page 62.
2.See “Removing the Lower Cover” on page 64.
3.See “Removing the WLAN Board Modules” on page 68.
4.See “Removing the Middle Cover and the Power Board” on page 78.
5.See “Removing the Keyboard” on page 79.
6.Remove the acetic tape and disconnect the LCD coaxial cable from the LCD1 connector on the main 
board.   
7.Remove the internal microphone cable from the INTMIC1 connector on the main board and release the 
cables from the latches.   
						

							82Chapter 3
8.Release the wireless LAN antenna cables from the hole and latches as shown.  
9.Remove the two screws (A) from the base of the unit. 
10.Remove the two screws (H) from the left and right hinge of the LCD module. 
StepSize (Quantity)ColorTo r q u e
1~2 M2.5 x L6 (2) Black 4.0 kgf-cm
StepSize (Quantity)ColorTo r q u e
1~2 M2.5 x L8 (2) Black 4.0 kgf-cm