Apple imac 17in 1ghz 服务手册

iMac (17-inch Flat Panel, 1GHz) Troubleshooting - 1

 General Information

General Information

Some of the key features that distinguish this computer from the earlier iMac (Flat Panel) models include:

1.

The diagnostic test points have moved on the bottom of the logic board. They are now located near the 

AirPort Extreme Card slot. Refer to the topic, “Diagnostic Test Points” in this chapter for more information.

2.

This computer uses double-data rate (DDR) memory; PC2100 DDR 266. Memory from previous iMac 

models is not compatible with this computer. Do not use older SDRAM DIMMs or SO-DIMMs even if they 

fit into the slot. Make sure to use PC2100 DDR 266 low profile SO-DIMMs in the user-installable slot. On 

the iMac (17-inch 1GHz) the memory pinouts are 184-pin internal, and 200-pin on the user-installable 

slot.

3.

There is an audio line in jack on the 17-inch, 1GHz model.

4.

The blind mate connector is gone, allowing easier assembly. The inverter, speaker, and fan cables are 

now part of the neck extension cables, replacing the blind mate connector.

5.

There are separate data cables for the optical and hard drive.

6.

 AirPort Extreme and built-in Bluetooth are CTO options.

7.

A clutch assembly was added to the door so it closes more quietly now.

8.

The Pangea heatsink on the logic board is about two inches longer.

9.

The diagnostic tool kit (cables), 076-0897, is not required anymore. The cables reach the logic board 

when the computer is in the open position, however; you may want to place something underneath the 

bottom housing (to prop it up) when the unit is open to give the cables some slack. 

Service items that still apply to all flat-panel iMac computers:

1.

Diagnostic test points are on to the logic board. They are accessed through the user access door. Use 

the test points to check the following:

• Battery

• 5V

• 12VSLP 

• 12V

For more information, refer to the “Logic Board Battery” and “No Power” topics later in this 
chapter.

2.

Important: The CPU uses a thermal pipe to transfer heat away. This pipe makes a thermal connection to 

the top metal chassis (Faraday cage) at two locations. These connecting points must be cleaned and