Apple imac 20 inch mid 2009 User Manual

 Apple Technician Guide
iMac (20-inch, Early/Mid 2009)
iMac (20-inch, Early 2009), iMac (20-inch, Mid 2009)
Updated:  2010-11-24  

 Apple Inc.
© 2009-2010 Apple Inc. All rights reserved.
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and...

iMac (20-inch, Early/Mid 2009)
About This Guide
Updates 8
Updated 24 November 2010  8
Updated 1 May 2009  8
Updated 28 April 2009  8
Introduced 3 March 2009  9
Feedback 9
Basics
Overview 11
Product Features  11
Differences Between Models  11
Product Configuration  12
Serial Number Location  12
Troubleshooting
General Troubleshooting  14
Update System Software & Firmware  14
Troubleshooting Theory  14
Hardware vs. Software  14
Apple Hardware Test  14
Apple Service Diagnostic  15
Common Reset Procedures...

Display 33
Backlight Issue/No Backlight  33
Incorrect/Missing Colors  38
Distorted/Blurred Image  39
Pixel Anomalies  41
Vertical/Horizontal Lines  42
Non-Uniform Brightness  44
Cosmetic Defects  45
Uncategorized Symptoms  45
Mass Storage 46
Hard Drive Not Recognized  46
Hard Drive Read/Write Error  48
Hard Drive Noisy  49
Optical Drive Not Recognized  51
Optical Drive Won’t Accept/Eject Media  52
Optical Drive Read/Write Error  54
Optical Drive Not Performing to Specifications  55
Optical Drive Noisy...

Take Apart
General Information 90
Opening the Unit 90
Required Tools  90
Required Special Tools for Glass Panel  91
Cleaning Tools Starter Kit  91
Cleaning & Handling the Glass Panel  92
Do’s and Don’ts  92
Handling a Broken Glass Panel  92
How to Remove a Broken Glass Panel  93
Safety 97
Logic Board Handling  98
Reassembly Steps  99
Images in This Guide  99
Screw Sizes  99
Access Door  100
Memory  101
Glass Panel  103
Removal 104
Reassembly  105
Front Bezel  109
Camera  112
Battery  114
IR (Infrared)...

Left Speaker 148
Ambient Temp Sensor Cable  150
CPU Fan  152
Right Speaker  154
Audio Board  156
Logic Board  159
Removal 160
Reassembly  161
Handling Logic Boards  163
Hard Drive Fan 164
Hard Drive Data Cable  166
Mechanism Cover  167
Stand  168
Mechanism  170
Chassis  172
Cable, DC, Power Supply/SATA/Inverter  175
Removal 176
Reassembly  178
Camera Cable  181
Microphone Cable  183
Rear Housing  185
Views
Exploded Views  187
iMac (20-inch, Early 2009), Part 1  187
iMac (20-inch, Early 2009), Part 2...

© 2009-2010 Apple Inc. All rights reserved.
 Apple Technician Guide 
About This Guide
iMac (20-inch, Early/Mid 2009)   

iMac (20-inch, Early/Mid 2009) — Updates 8 2010-11-24
Updates
Updated 24 November 2010
Troubleshooting:
• General: Updated information and links for Updating System Software & Firmware, 
Troubleshooting Theory, and Common Reset Procedures.
•  Startup and Power: No Power, Dead Unit: Step 6: Yes: Changed action to “Go to step 7.”
•  Startup and Power: Intermittent Shutdown: Step 1: Updated information about which 
console log to check for OS 10.6 vs. OS 10.5 and earlier.
Take Apart:
•  General:
•  Updated...

iMac (20-inch, Early/Mid 2009) — Feedback 9 2010-11-24
• Block Diagram: Added note that Mid 2009 model does not have IR or Bluetooth.
Take Apart:
•  Front Bezel: Added reassembly note to install bottom of bezel first.
•  Camera Board: Corrected screw size and part number.
•  IR Board: Added note that Mid 2009 model does not have an IR Board.
•  Bluetooth Board: Added note that Mid 2009 model does not have a Bluetooth Board.
•  Optical Drive: Added reassembly note to avoid trapped inverter cables.
•  Hard...

© 2009-2010 Apple Inc. All rights reserved.
 Apple Technician Guide 
Basics
iMac (20-inch, Early/Mid 2009)