Apple Technician Guide for iMac (21.5-inch, Mid 2011)

263 Pages·2011·33.11 MB·English

 Apple Technician Guide
iMac (21.5-inch, Mid 2011)
Updated: 2011-05-24
 Apple Inc.
© 2011 Apple Inc. All rights reserved.
Under the copyright laws, this document may not be copied, in whole or in part, without the
written consent of Apple.
Every effort has been made to ensure that the information in this document is accurate. Apple
is not responsible for printing or clerical errors.
Apple
1 Infinite Loop
Cupertino, CA 95014-2084
USA
+ 1 408 996 1010
www.apple.com
Apple, the Apple logo, Mac, and Macintosh are trademarks of Apple Inc., registered in the U.S.
and other countries.
iMac (21.5-inch, Mid 2011)
Contents
About This Guide
Updates 9
Updated 24 May 2011 9
Introduced 04 May 2011 9
Feedback 10
Basics
Overview 12
Identifying Features 13
Product Configurations 13
Thunderbolt 14
Safety Precautions 15
Serial Number Location 16
Troubleshooting
General Troubleshooting 18
Update Software & Firmware 18
Wireless Troubleshooting 18
Troubleshooting Theory 18
Hardware vs. Software 18
Common Reset Procedures 19
Power On Self Test (POST) 19
Starting Up in Safe Mode 19
Resetting the System Management Controller (SMC) 20
Resetting Parameter RAM (PRAM) 20
Coin Battery Removal, Testing, and PRAM Reset 21
Recovering a Lost Firmware Password 21
Diagnostics 22
Sensor Errors 22
Sensor and Fan Connector Locations 25
Diagnostic LEDs 26
LED Startup Sequence 27
Block Diagram 28
Functional Overview 29
Symptom Charts 31
Startup and Power 31
No Power 31
No Startup 33
Intermittent Shutdown 35
Kernel Panic / System Crashes 40
No Video 42
Corrupted Video 44
Burnt Smell/Odor 47
Uncategorized Symptoms 48
Display 49
Backlight Issue/No Backlight 49
Noise / Unstable Flickering 51
Incorrect/Missing Colors 55
Distorted/Blurred Image 56
Pixel Anomalies 58
Vertical/Horizontal Lines 59
Non-Uniform Brightness / Color 61
Cosmetic Issues 62
Uncategorized Symptoms 62
Mass Storage 63
Hard Drive or SSD Not Recognized 63
Hard Drive Read/Write Errors 65
Hard Drive Noisy 67
Optical Drive Not Recognized 69
Optical Drive Rejects or Does Not Accept Media 71
Optical Drive Read/Write Error 73
Optical Drive Not Performing to Specifications 75
Optical Drive Noisy 77
SD Memory Card Cannot Be Inserted Into Slot 79
SD Memory Card Not Recognized 80
Uncategorized Symptoms 82
Communications 83
AirPort Issues 83
Deep Dive 85
Bluetooth Issues 86
AirPort Card Kernel Panic 88
Ethernet Issues 89
Wireless Input Device Does Not Pair 91
Uncategorized Symptoms 93
Input/Output Devices 94
Apple Remote Issues 94
Distorted Audio From Internal Speaker(s) 98
No Audio From Internal Speaker(s) 99
Camera Issues 101
USB Port Not Recognized 104
Wired Keyboard Does Not Work Properly 106
Keyboard: Specific Keys Do Not Respond 108
Wired Keyboard/Mouse Not Recognized 108
Wireless Input Device Does Not Pair 110
Apple Wireless Mouse/Magic Trackpad Erratic Tracking 112
Wireless Input Device Loses Connection 113
Mechanical 117
Noise/Hum/Vibration 117
Fan Failures / Thermal Issues 120
Stand/Hinge Issues 122
Uncategorized Symptoms 122
Take Apart
General Information 124
Opening the Computer 124
Required Tools 124
Required Special Tools for Glass Panel 125
Cleaning Tools Starter Kit 125
Cleaning & Handling the Glass Panel 126
Do’s and Don’ts 126
Handling a Broken Glass Panel 126
How to Remove a Broken Glass Panel 127
Safety 131
Logic Board Handling 132
Reassembly Steps 132
Note About Images in This Guide 132
Screw Sizes 132
Access Door 133
Memory 135
Glass Panel 137
Removal 138
Reassembly 139
LCD Panel 142
Handling LCD Panel 146
Vertical Sync (V-Sync)/
Temp Sensor Cable 148
DisplayPort Cable 151
DisplayPort Power Cable 153
Battery 155
AirPort Card 157
Bluetooth Board 159
Bluetooth Antenna 161
Camera 163
LED Backlight Board 166
Power Supply 168
Backlight Pressure Wall 170
Hard Disk Drive (HDD) 172
Power Supply Pressure Wall 175
Bluetooth/Camera/Sensor Cable 177
Skin Temp Sensor Cable 181
AirPort Antenna, Top Right 183
AirPort Antenna, Left Side 185
Optical Disc Drive (ODD) 187
Optical Drive Sensor Cable 190
Solid State Drive (SSD) 192
Optical Drive Fan 195
SD Card Reader 197
SD Card Reader Cable 199
Audio Ports & Cable 201
IR Board & Cable 203
Logic Board 205
Video Card 213
Video Card Bracket 215
ODD Data/Power Cable 217
HDD Data Cable 219
HDD Power Cable 221
SSD Data Cable 224
SSD Power Cable 226
DC Power Cable 228
Optical Drive Pressure Wall 231
Hard Drive Fan 233
CPU Fan 235
Left Speaker 238
Right Speaker 241
Mechanism Cover 243
Stand 245
Mechanism 247
Rear Housing 249
Views
Exploded Views 253
iMac (21.5-inch, Mid 2011), Part 1 253
iMac (21.5-inch, Mid 2011), Part 2 254
iMac (21.5-inch, Mid 2011), Part 3 255
Screw Chart 256
External Views 258
Front View 258
Rear View 259
I/O Ports 260
Internal Views 261
Components Below LCD 261
Components Below Logic Board 262
Logic Board, Front Side 263
Logic Board, Back Side 263
 Apple Technician Guide
About This Guide
iMac (21.5-inch, Mid 2011)
© 2011 Apple Inc. All rights reserved.
Updates
Updated 24 May 2011
Basics:
• Safety: Modified text and image to indicate voltage warning applies to both Power Supply
and LED Backlight Board.
Take Apart:
• Added chapters for Solid State Drive, SSD Data Cable, and SSD Power Cable.
• Hard Disk Drive (HDD): Added Note: This model may have a hard drive and/or a solid state
drive (SSD) installed. The SSD (if present) is located underneath the optical drive.
• Logic Board:
• Added Caution: HDD power cable (17) has an identical connector to DC power
cable (24). You can differentiate these cables by the length of the wires between the
connector and sheathing. It is VERY IMPORTANT to plug these connectors into the
proper ports on the logic board. Plugging either cable into the wrong port can
lead to logic board failure.
• Added image to help differentiate HDD Power Cable from DC Power Cable.
• Added Note: Depending on the configuration, there may be HDD and/or SSD cables.
If both are present, make sure HDD data and SSD data cables are connected to their
proper respective ports.
• Added instructions to transfer HDD Power Plug in configurations that have only a Solid
State Drive (no Hard Drive).
• Optical Drive Pressure Wall: Modified Step 1 to describe how SSD cables route through
notches in pressure wall.
Views:
• Exploded Views: Added Solid State Drive, SSD Data Cable, SSD Power Cable, and HDD Power
Plug.
• Screw Chart: Added screws for Solid State Drive.
Introduced 04 May 2011
2011-05-24 iMac (21.5-inch, Mid 2011) About This Guide — Updates 9
Feedback
We want your feedback to help improve this and future Technician Guides!
Please email any comments to: [email protected]
2011-05-24 iMac (21.5-inch, Mid 2011) About This Guide — Feedback 10