Apple imac usb 2 0 User Manual

							
 
52 -  
 iMac (USB 2.0)  Take Apart  Optical Drive Door 
Optical Drive Door 
Tools 
This procedure requires the following tools:
• Torx-10 screwdriver
• Needlenose pliers 
Part Location
Preliminary Steps 
Before you begin, do the following:
• Position the computer in the service stand.
• Remove the user access plate.
• Remove the bottom housing.
• Remove the drive carrier assembly. 
						

							
 
 iMac (USB 2.0)  Take Apart -   
53
 
 Optical Drive Door 
Procedure 
1. Remove four screws on the power supply shield. Set the shield aside. 
 
Important:
 
 The two screws near the door hinge are shorter than the other power 
supply screws. Failure to replace the shorter screws to their correct location will 
scratch the top housing. See the Power Supply topic, step 4, Replacement Note, for a 
picture of what happens when the wrong screws are inserted in the wrong location.  
						

							
 
54 -  
 iMac (USB 2.0)  Take Apart  Optical Drive Door
2. Slide the optical door guide off the chassis and the door hinge tabs (c\
ircled). 
3. Carefully remove the two door springs with a needlenose pliers.  
						

							
 
 iMac (USB 2.0)  Take Apart -   
55  
 Optical Drive Door 4. Remove the door hinge screws.
5. Open the door. 
						

							
 
56 -  
 iMac (USB 2.0)  Take Apart  Optical Drive Door
6. Slide the door and hinge off the chassis. 
 
Warning:  
 Whenever the bottom housing is opened for service, you must do two things:
1.You must clean the original thermal film from all thermal interface ma\
ting surfaces, 
and reapply thermal paste to the mating surfaces on the thermal pipe.
2. You must tighten the four torx screws on the bottom housing to a mini\
mum of 17 
in.-lbs. Use a torque driver (service tool 076-0899) to ensure that th\
e thermal pipe is 
firmly mated with the top base. If you do not have a torque driver, you \
must make 
sure the screws are tightened by hand FIRMLY, BUT NOT FORCIBLY.   
Failure to follow these steps could cause the computer to overheat and 
damage internal components.  
Refer to the topic “Thermal Paste Application” for detailed inform\
ation. 
						

							
 
 iMac (USB 2.0)  Take Apart -   
57  
 Speaker, Internal 
Speaker, Internal
Tools
This procedure requires the following tools:
• Torx-10 screwdriver
Part Location
Preliminary Steps
Before you begin, do the following:
• Position the computer in the service stand.
• Remove the user access plate.
• Remove the bottom housing.
• Remove the drive carrier assembly. 
						

							
58 - iMac (USB 2.0)  Take Apart
 Speaker, Internal
Procedure
1. Loosen the two screws enough to slide the speaker off the metal posts. Disconnect 
the speaker cable.
Warning:  Whenever the bottom housing is opened for service, you must do two things:
1.You must clean the original thermal film from all thermal interface ma\
ting surfaces, 
and reapply thermal paste to the mating surfaces on the thermal pipe.
2. You must tighten the four torx screws on the bottom housing to a mini\
mum of 17 
in.-lbs. Use a torque driver (service tool 076-0899) to ensure that th\
e thermal pipe is 
firmly mated with the top base. If you do not have a torque driver, you \
must make 
sure the screws are tightened by hand FIRMLY, BUT NOT FORCIBLY. 
Failure to follow these steps could cause the computer to overheat and 
damage internal components.
Refer to the topic “Thermal Paste Application” for detailed inform\
ation. 
						

							
 iMac (USB 2.0)  Take Apart - 59
 Fan
Fan
Tools
This procedure requires the following tools:
• Torx-15 screwdriver
Part Location
Preliminary Steps
Before you begin, do the following:
• Position the computer in the service stand.
• Remove the user access plate.
• Remove the bottom housing.
• Remove the drive carrier assembly. 
						

							
60 - iMac (USB 2.0)  Take Apart
 Fan
Procedure
1. Remove the two fan screws and disconnect the fan connector. 
2. Pull the fan out of the chassis (Faraday cage). Note: The replacement fan includes the 
mounting bracket.
3. Note:  The fan on the 20-inch iMac (USB 2.0), 922-6215, is different (identify by the 
amps highlighted below) from the fan used on the 15-inch and the 17-inch iMac (USB 
2.0) computers. The 20-inch iMac (USB 2.0) fan is shown below.    
						

							
 iMac (USB 2.0)  Take Apart - 61
 Fan Warning:
 Whenever the bottom housing is opened for service, you must do two things:
1.You must clean the original thermal film from all thermal interface ma\
ting surfaces, 
and reapply thermal paste to the mating surfaces on the thermal pipe.
2. You must tighten the four torx screws on the bottom housing to a mini\
mum of 17 
in.-lbs. Use a torque driver (service tool 076-0899) to ensure that th\
e thermal pipe is 
firmly mated with the top base. If you do not have a torque driver, you \
must make 
sure the screws are tightened by hand FIRMLY, BUT NOT FORCIBLY. 
Failure to follow these steps could cause the computer to overheat and 
damage internal components.
Refer to the topic “Thermal Paste Application” for detailed inform\
ation.