Apple ibook g4 12 inch late 2004 User Manual

							 
iBook G4 (12-inch Late 2004) Troubleshooting - 
 
9
 
 Symptom Charts
 
Startup
 
The computer will not power on
 
1. Remove any connected peripherals.
2. Try known-good power outlet.
3. Try known-good power adapter and power cord.
4. Remove battery.
5. Reset the power manager by pressing the key combination Control-Option-Shift-
power. 
 
Warning: Make sure you do not hold down the fn key when resetting the 
power manager.
Warning: Resetting the power manager means you will also need to reset the 
date and time (using the Date & Time control panel).
 
6. Reset PRAM (Press the power button, then hold down the Option-Command-P-R 
keys until you hear the startup chime at least one additional time after the initial 
startup chime).
7. Disconnect internal keyboard completely. Inspect connectors. Restart with keyboard 
disconnected.
8. Remove any additional RAM and AirPort Extreme Card.
9. Try known-good DC board.
10. Verify cable connections and check cables for damage.
11. Verify power button is connected properly to logic board, if power button is not 
functioning correctly or damaged, replace the top case.
12. Replace logic board.
 
At startup, a dialog box comes up stating “kernel panic” in Mac OS X 
 
1. If a RAM card is installed in the expansion slot, remove it and restart.
• If symptom repeats, replace logic board.
• If symptom does not repeat, replace RAM card with known-good RAM card; restart.
2. If no RAM card is installed, replace logic board.
Related article:
111772: iBook (Dual USB): Beeps Are Heard at Startup (one to four beeps) 
						

							 
10 - 
 
iBook G4 (12-inch Late 2004) Troubleshooting
 Symptom Charts
 
Display
 
No display, or dim display, but computer appears to operate correctly
 
1. Remove any connected peripherals.
2. Try known-good power outlet, power adapter and power cord.
3. Press F2 (with the fn key pressed and not pressed) to increase the screen brightness 
setting.
4. Reboot the computer—hold down the Control and Command keys and press the 
Power button, or press and hold the Power button for 5 to 10 seconds to shut down the 
computer, then press the Power button to restart.
5. Reset the power manager by pressing the key combination Control-Option-Shift-
power. 
 
Warning: Make sure you do not hold down the fn key when resetting the 
power manager.
Warning: Resetting the power manager means you will also need to reset the 
date and time (using the Date & Time control panel).
 
6. Reset PRAM (Press the power button, then hold down the Option-Command-P-R 
keys until you hear the startup chime at least one additional time after the initial 
startup chime).
7. Connect an external display, and check for video on external display.
• If video is fine on external display, replace LCD panel.
• If video symptom is same on external display, replace logic board.
8. Verify backlight cable and LVDS cable connections are seated properly and that the 
cables are not damaged (refer to display assembly replacement instructions).
9. Replace LCD panel.
10. Verify cable connections and check cables around the hinges for damage.
11. Replace logic board.
 
When displaying a single color over the screen area, the LCD panel shows one 
or more pixels that are not properly lit
 
Active-matrix LCD technology uses rows and columns of addressable locations (pixels) 
that render text and images on screen. Each pixel location has three separate subpixels 
(red, green, and blue) that allow the image to be rendered in full color. Each subpixel has a 
corresponding transistor responsible for turning the subpixel on or off.
There are typically millions of these subpixels on an LCD display. For example, the LCD 
panel used in the Apple Cinema HD display is made up of 2.3 million pixels and 6.9 million 
red, green, and blue subpixels. Occasionally, a transistor does not work perfectly, which 
may result in the affected subpixel being turned on (bright) or turned off (dark). With the  
						

							 
iBook G4 (12-inch Late 2004) Troubleshooting - 
 
11
 
 Symptom Chartsmillions of subpixels on a display, it is quite possible to have a low number of faulty 
transistors on an LCD. Therefore, a certain number of subpixel anomalies is considered 
acceptable. Rejecting all but perfect LCD panels would significantly increase the retail 
price for products using LCD displays. These factors apply to all manufacturers using LCD 
technology—not just Apple products.
To determine whether or not the display has an acceptable number of pixel anomalies, 
follow the steps below:
1. Set the display image to one of the following colors: all-white display, all-red display, 
all-green display, or all-blue display.
2. Using a jeweler’s loupe, pocket microscope, or other magnifying device, identify and 
count each subpixel anomaly:
• Bright subpixel anomaly = subpixel that is always on
• Dark subpixel anomaly = subpixel that is always off
3.
 
Important:
 
 Check the number of subpixel anomalies with the following chart:
4. If the number of subpixel anomalies exceeds the acceptable number listed in the 
chart, replace the LCD panel.
5. If the number of subpixel anomalies is acceptable, explain to the customer that the 
pixel anomalies are within specifications, and no repair is necessary. 
 
Important:
 
  Do not release the specifications to customers. Instead, inform them that 
a certain number of subpixel anomalies is considered acceptable, and these factors 
apply to all manufacturers using LCD technology—not just Apple products.
 
Scrambled or distorted video
 
Check for video on external display.
• If video is fine on external display, replace LVDS cable.
• If video is scrambled or distorted on external display, replace LCD panel.
 
Video (S-Video and Composite adapter)
 
No video on an external device
 
1. Make sure you are using the S-Video and Composite adapter cable.
2. Verify TV or VCR is set up properly with correct source.
3. Try different TV or VCR. Check owner’s manual for TV or VCR.
 
LCD Size 
(inches)Acceptable Number of Subpixel 
AnomaliesReplace the LCD Panel
 
BrightDark CombinationBrightDark Combination
12.1 to 15.2 up to 3 up to 5 up to 7 4 or more 6 or more 8 or more 
						

							 
12 - 
 
iBook G4 (12-inch Late 2004) Troubleshooting
 Symptom Charts 4. Replace adapter cable.
5. Replace logic board. 
 
The display is rolling (PAL instead of NTSC)
 
1. Make sure you are not using Apples A/V Video Cable.
2. Make sure you are using the S-Video and Composite adapter cable.
3. In Mac OS X, go to the Displays system preference to change the setting.
4. Try a different TV or VCR.
5. Try a different adapter cable.
6. Replace logic board.
 
Display shows ghosting (signal reflection) 
 
1. Verify that cables are correctly installed and firmly seated.
2. Replace video adapter.
 
Video (VGA adapter)
 
No video on an external device
 
1. Verify monitor that is used in testing is known-good and is supported by this computer.
2. Try known-good VGA adapter.
3. Replace logic board.
4. Replace VGA adapter cable.
5. Replace logic board. 
 
Display shows ghosting (signal reflection) 
 
1. Verify that cables are correctly installed and firmly seated.
2. Replace video adapter.
 
Misc. Symptoms
 
The computer runs with battery, but not with the power adapter plugged into 
wall outlet
 
1. Try known-good power outlet. 
2. Try known-good power adapter and power cord. 
3. Reset the power manager by pressing the key combination Control-Option-Shift-
power.  
						

							 
iBook G4 (12-inch Late 2004) Troubleshooting - 
 
13
 
 Symptom Charts
 
Warning: Make sure you do not hold down the fn key when resetting the 
power manager.
Warning: Resetting the power manager means you will also need to reset the 
date and time (using the Date & Time control panel).
 
4. Replace the DC board. 
5. Replace the logic board. 
Related article:
88133: iBook (Dual USB): Using PowerBook G4 Adapter
 
The computer runs when plugged into a wall outlet but not on battery power
 
1. Reseat battery to verify battery is seated correctly with battery lock engaged.
2. Try known-good charged battery.
3. Reset the power manager by pressing the key combination Control-Option-Shift-
power. 
 
Warning: Make sure you do not hold down the fn key when resetting the 
power manager.
Warning: Resetting the power manager means you will also need to reset the 
date and time (using the Date & Time control panel).
 
4. Replace logic board.
 
The cursor does not move when you are using trackpad
 
1. Verify that no USB device is connected.
2. Boot from a Mac OS system CD to verify that it is not a software problem.
3. Reset the power manager by pressing the key combination Control-Option-Shift-
power. 
 
Warning: Make sure you do not hold down the fn key when resetting the 
power manager.
Warning: Resetting the power manager means you will also need to reset the 
date and time (using the Date & Time control panel).
 
4. Check trackpad cable and connection to the logic board (see separate Top Case 
replacement instructions for location under RAM shield).
5. Replace top case.
6. Replace logic board. 
						

							 
14 - 
 
iBook G4 (12-inch Late 2004) Troubleshooting
 Symptom Charts
 
The cursor intermittently does not move or moves erratically
 
Note:
 
 User must touch with only one finger at a time and point directly down on the 
trackpad surface.
1. Clean trackpad surface (with computer off, using a non-static-inducing material).
2. Reset the power manager by pressing the key combination Control-Option-Shift-
power. 
 
Warning: Make sure you do not hold down the fn key when resetting the 
power manager.
Warning: Resetting the power manager means you will also need to reset the 
date and time (using the Date & Time control panel).
 
3. Reset PRAM (Press the power button, then hold down the Option-Command-P-R 
keys until you hear the startup chime at least one additional time after the initial 
startup chime).
4. Remove and reseat memory card.
5. Try unit on battery power. If problem goes away, replace power adapter.
6. Place a Mac OS system CD in the optical disc drive, press the start button and hold 
down the “C” key. Check the cursor movement, to see if the problem is software.
7. Check trackpad cable and connection to the logic board (see separate Top Case 
replacement instructions for location under RAM shield).
8. Replace top case.
9. Reseat the heatsink if it is not properly secured.
10. Replace logic board.
 
The microphone is not working
 
1. Check the signal level and level meter and adjust the gain.
2. Reset PRAM (Press the power button, then hold down the Option-Command-P-R 
keys until you hear the startup chime at least one additional time after the initial 
startup chime).
3. Verify microphone cable connection to logic board, and check cable for damage.
4. Replace microphone cable.
5. Replace logic board. 
						

							 
iBook G4 (12-inch Late 2004) Troubleshooting - 
 
15
 
 Symptom Charts
 
The latching mechanism that holds the display closed is not working
 
Note: 
 
As the display closes against the top case, a hook in the top of the display housing 
should be magnetically pulled down into a slot in the top case, and secured. When the 
latch button is pushed, the hook should release and retract into the display housing, 
allowing the display to open.
1. Verify hook operation by exercising the latch mechanism. 
2. If the hook does not operate properly, replace the display bezel.
3. If the latch or latch button does not operate properly, replace the top case assembly.
 
Fan fails
 
1. Check fan cable connection, and check cable for damage.
2. Replace fan.
3. Replace logic board.
 
Trackpad works intermittently
 
The trackpad operation can be affected by hand lotion, humidity, dangling jewelry, and the 
use of more than one finger on the trackpad. 
1. Check for environmental factors such as humidity, hand lotion, or jewelry.
2. Clean the trackpad with a clean, dry lint-free cloth. 
Related articles:
17228: Portables: Jumpy or Erratic Trackpad Operation
58389: PowerBook and iBook: Trackpad Does Not Respond
 
Greasy substance in battery bay
 
A small amount of grease is used on the springs in the battery bay. Inform customers that 
the grease helps the springs operate correctly. The grease is not harmful and should not 
cause alarm. However, if it comes in contact with skin, wash it off with soap and water.
Refer to Knowledge Base article 88369: iBook: White Greasy Substance in Battery Bay. 
						

							 
16 - 
 
iBook G4 (12-inch Late 2004) Troubleshooting
 Symptom Charts
 
Block Diagram
External
display
connector
Ethernet port FireWire port
Internal
speakers Headphone port
Internal
microphone AGP 4X
bus
Memory bus133 MHz
MaxBus
PMU99
power controller
Trackpad
Keyboard
Power supply and charger
SO-DIMM connector
ATI Mobility
Radeon 9200
graphics IC
Flat-panel
display
Audio
system
Ethernet
PHY
FireWire
PHY
PowerPC G4
microprocessor
(L2 cache: 512 KB)
256 MB on-board
SDRAM
PCI bus
Boot
ROM
USB 2.0 port
USB 2.0 port
PCI USB
controller
AirPort
Extreme
Card
ATA-100 bus
ATA-33 bus Connector to internal
IDE disk drive
Connector to internal
optical drive
I2S
12 Mbps USBModem port
Modem moduleBluetooth
Data pump
and DAA
Intrepid
memory
controller
and I/O
device
controller 
						

							 
© 2004 Apple Computer, Inc. All rights reserved.
 

 
 
 
Service Source
Views
 
                  iBook G4 (12-inch Late 2004) 
						

							 
iBook G4 (12-inch Late 2004) Views - 
 
1
 
 
 
Slot-Load Optical Drive Side View
Ports Side View
Bottom Case View