Apple iMac (USB 2.0) 03 Service Manual

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Service Source

iMac (USB 2.0)

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Service Source

Basics

iMac (USB 2.0)

Overview

The iMac (USB 2.0) computers are powered by the PowerPC G4 processors. Two models are available: the 17-inch widescreen LCD (1.25 GHZ) or the 15-inch LCD ﬂat screen (1 GHz). The computer also includes 80GB hard drives, 256MB DDR333 SDRAM, two FireWire 400 ports and three USB 2.0 ports. The 17-inch widescreen and the 15-inch ﬂat panel computers come with Mac OS X version 10.2.7 installed as the default system .

Overview

How to identify these models

Verify the processor speed. If the system is up and running, select “About this Mac” under the Apple icon in the Finder. Or, select the “More Info” button on the “About this Mac” window. Apple System Proﬁler opens and displays the machine speed under “Hardware Overview.” The 15-inch iMac has a 1GHz PowerPC G4 processor and the 17-inch iMac has a 1.25GHz PowerPC G4 processor.

iMac (USB 2.0) Basics - 1

What’s New

New Features

Processor and speed —The microprocessor in the iMac (Flat Panel, USB 2.0) is a

PowerPC G4 with a clock speed of 1 GHz in the 15" conﬁguration and a 1.25 GHz in the 17" conﬁguration.

USB 2.0 ports — The computer has three USB 2.0 ports.

Memory — This computer comes with 256 MB of DDR333 SDRAM installed in an internal

standard 186-pin DIMM expansion slot, with a build-to-order options of 512 MB . A second user-accessible slot accepts an SO-DIMM with up to 512 MB. The maximum total memory is 1 GB.

System bus — The speed of the system bus is 167 MHz.

Graphics acceleration — The A GP 4X g raphics IC used is either an NVidia GeF orce4MX

or and NVidia GeForce FX5200 Ultra.

Video RAM — The video hardware includes either 32 MB or 64 MB of DDR SDRAM,

which supports 3D features and millions of colors in all resolutions.

External video monitor — The e xternal display connector supports mini-VGA, composite,

S-video monitors and projectors, and television sets. A video adapter with composite and S-video connectors and a VGA-out adapter are available separately.

Bluetooth support (optional) — Bluetooth support is available as a build-to-order option

to enable short-range wireless connections between desktop and laptop computers and a host of other peripheral devices.

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What’s New

Standard Conﬁgurations

Features 15-inch 17-inch

CPU and speed

System bus speed Main memory

Display

Graphics IC

Graphics memory Hard disk drive

Optical drive External monitor

adapter

Communication features

1GHz PowerPC G4 1.25GHz PowerPC G4

167 MHz 167 MHz 256 MB SDRAM,

expandable up to 1 GB 15-inch ﬂat panel 17-inch, wide-screen ﬂat

NVIDIA GeForceMX NVIDIA GeForce FX

32 MB DDR RAM 64 MB DDR RAM 80 GB Ultra A TA-66 7200

rpm

Tray-load Combo drive Tray-load SuperDrive Mini-VGA or S-video/

composite

10/100 Ethernet; 56K V.92 fax modem

256 MB SDRAM, expandable up to 1 GB

panel

5200 Ultra

80 GB Ultra A TA-66 7200 rpm

Mini-VGA or S-video/ composite

10/100 Ethernet; 56K V.92 fax modem

What’s New

Wireless features

Optional 54 Mbps AirPort Extreme Card; optional internal Bluetooth

iMac (USB 2.0) Basics - 3

Serial Number Location

To identify a particular model of iMac (USB 2.0), check the computer’s serial number, which lists the model’s conﬁguration. The serial number is located on the bottom of the computer, on the metal access plate, or on the inside of the optical drive door (bottom photo).

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Serial Number Location

iMac (USB 2.0) Basics - 5

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Service Source

Take Apart

iMac (USB 2.0)

General Information

Overview

The Take Apart chapter includes take apart procedures for both the 15" and 17" iMac (USB 2.0) computers. If you are f amiliar with taking apart iMac (Flat Panel) computers, y ou will ﬁnd that the procedures for these newer models haven’t changed. The changes consist of faster processors, f aster system bus , larger capacity hard drives, and three USB

2.0 ports.

New Procedures

The following Take Apart sections were updated:

• Display, Inverter, Back Cover, and the Neck Assembly

Tools

The following tools are recommended for the take apart procedures.

• The service stand (076-0898)

• Thermal paste (922-4757)

•

Torque driver, 17" LB (076-0899)

• 1.5 mm hex driver (for LCD bezel screws)

• #0 Phillips screwdriver)

• Torx screwdriver set (6, 8, 10, 15)

• Plastic flatblade screwdriver or stylus (922-5065)

• Needlenose pliers

• ESD wriststrap and mat

General Information

iMac (USB 2.0) Take Apart - 1

Service Stand

1. Support the computer by neck and the base (A). Gently position the computer in the service stand with the ﬂat panel facing up (B).

2. Note: The base of the computer can be rotated when servicing internal parts.

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General Information

User Access Plate

Tools

This procedure requires the following tools:

• Phillips #0 screwdriver

Part Location

User Access Plate

Preliminary Steps

Before you begin, do the following:

• Position the computer in the service stand.

iMac (USB 2.0) Take Apart - 3

Procedure

1. Loosen the four captive screws on the access panel.

2. Remove the panel by grabbing onto two captive screws and lift the panel off the base.

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User Access Plate

AirPort Extreme Card

Tools

This procedure requires no tools.

Part Location

Preliminary Steps

Before you begin, do the following:

• Position the computer in the service stand.

• Remove the user access plate.

AirPort Extreme Card

iMac (USB 2.0) Take Apart - 5

Procedure

1. Unplug all cables from the computer except the power cord.

Important: To avoid electrostatic discharge, always ground yourself by touching

2. metal before you touch any parts or install any components inside the computer. To avoid static electricity building back up in your body, do not walk around the room until you have completed the installation and closed the computer.

3. Touch a metal surface inside the computer to ground yourself.

4. Unplug the power cord.

5. Pull the plastic tab on the AirPort Extreme card to remove it from the slot. Disconnect the AirPort antenna from the card.

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AirPort Extreme Card

Memory, SO-DIMM (userinstallable)

Tools

No tools are required for this procedure.

Part Location

Preliminary Steps

Before you begin, do the following:

• Position the computer in the service stand.

• Remove the user access plate.

Note: DIMMs used in this slot should be a low-proﬁle PC2700 (DDR333) SO-DIMM. Only

the SO-DIMM slot is accessible by the user.

Memory, SO-DIMM (user-installable)

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Procedure

1. Unplug all cables from the computer except the power cord.

Important: To avoid electrostatic discharge, always ground yourself by touching

2. metal before you touch any parts or install any components inside the computer. To avoid static electricity building back up in your body, do not walk around the room until you have completed the installation and closed the computer.

3. Touch a metal surface inside the computer to ground yourself.

4. Unplug the power cord.

5. Release the memory by spreading apart the tabs in the expansion slot from the notches in the card.

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Memory, SO-DIMM (user-installable)

6. Allow the memory to pop up slightly, and pull it out of the memory slot.

Memory, SO-DIMM (user-installable)

iMac (USB 2.0) Take Apart - 9

Bottom Housing

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.

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Bottom Housing

Procedure

1. When opening the bottom housing, rotate the base so the optical drive door is on the right. (This position is less stressful on the internal cables when the bottom is open).

2. Remove the four torx screws.

Replacement Note:

not have a torque driver, you will have to make sure these screws are tightened by hand FIRMLY, BUT NOT FORCIBLY. Or, purchase the service tool (076-0899) in order to ensure the thermal pipe is ﬁrmly mated with the top base. If the bottom housing is not securely attached to the base in this fashion, the CPU may overheat and become damaged. For more information, refer to “Thermal Paste Application’” in this chapter. Rotate the base so that the optical drive door is on the right.

These torx screws must be tightened to at least 17 in.-lbs. If you do

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3. Gently open the bottom housing in the direction of the arrow. Disconnect the cables.

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4. Disconnect the following:

C

D

E

A

Grounding screw

B

Bluetooth connector (if Bluetooth board is present, this will be connected)

AirPort connector

AC line filter connector

TMDS video connector

F Inverter, speaker, fan connector G Optical cable and connector H Hard drive cable and connector I Power Supply connector

5. Set the bottom housing aside.

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 mating 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 minimum of 17 in.-lbs. Use a torque driver (service tool 076-0899) to ensure that the 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 information.

iMac (USB 2.0) Take Apart - 13

Thermal Paste Application

Tools

This procedure requires the following tools:

• Plastic stylus or plastic spatula to remove the old thermal paste

• Plastic stylus or plastic spatula to spread the thermal paste

• Thermal paste (922-4757)

Part Location

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Thermal Paste Application

Procedure

1. Thoroughly clean the original thermal ﬁlm from the mating surfaces (circled below) of the bottom housing and thermal pipe. Use a plastic stylus to scrape the surfaces clean. Note: Do not use an abrasive material or liquid cleaner.

2. Squeeze a ball of thermal paste onto the mating surfaces of the thermal pipe.

Thermal Paste Application

iMac (USB 2.0) Take Apart - 15

3. Replace the bottom housing. Warning: The bottom housing has four torx screws that must be tightened to at least

17 in.-lbs. Use a torque driver (service tool 076-0899) to ensure that the 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 apply the thermal paste as described in this procedure, and failure to tighten the torx screws as directed, could cause the computer to overheat and damage internal components.

Refer to the topic “Thermal Paste Application” for detailed information.

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Thermal Paste Application

RJ-11 Modem Filter Board

Tools

This procedure requires the following tools:

• Torx-6 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.

RJ-11 Modem Filter Board

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Procedure

1. Remove two screws and disconnect the cable from the modem.

2. Remove the RJ-11 board from the I/O port.

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 mating 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 minimum of 17 in.-lbs. Use a torque driver (service tool 076-0899) to ensure that the 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 information.

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RJ-11 Modem Filter Board

Modem

Tools

This procedure requires the following tools:

• Torx-8 screwdriver

Part Location

Modem

Preliminary Steps

Before you begin, do the following:

• Position the computer in the service stand.

• Remove the user access plate.

• Remove the bottom housing.

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Procedure

1. Remove two screws and disconnect the cable.

2. Lift the modem board from the connector on the logic board.

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 mating 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 minimum of 17 in.-lbs. Use a torque driver (service tool 076-0899) to ensure that the 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 information.

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Modem

Memory (factory-installed)

Tools

This procedure requires the following tools:

• No tools are required

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.

Memory (factory-installed)

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