Apple power mac g4 fw 800 User Manual

							
 
Power Mac G4 (Mirror/FW800) Troubleshooting -   
17
 
 Symptom Charts 
System shuts down when using multiple FireWire devices and an Apple ADC 
17 CRT display is connected
 
The power requirements for multiple FireWire devices and the Apple ADC 17 CRT display 
may exceed the capacity of the power supply, causing it to shut the system down. To 
alleviate this problem, do the following: 
1. Reduce the number of bus-powered FireWire devices 
2. Use a power adapter with all FireWire devices 
3. Reduce monitor power draw by reducing brightness or reducing the amount of white  space (open text documents, for example).  
System quits or stops responding intermittently
 
1. If the system quits or stops responding in a speci fic application, force the application 
that has frozen to quit:
• In Mac OS X, choose Force Quit from the Apple menu and select the applic\
ation.
• In Mac OS 9, hold down the Esc, Option and Command keys and click Force \
Quit  in the dialog box.
Replace the application. Verify the application is compatible with the o\
perating 
system.
2. For a suspected software problem,  • Use Software Update to ensure that the computer has the latest drivers, \
bug fixes, and other updates.
• For problems with software from a manufacturer other than Apple, contact\
 the  manufacturer. 
3. Clear parameter RAM. Hold down Command-Option-P-R during startup until you hear  a second startup chime.
4. Perform a clean install of system software with the system restore CD that came with  the computer.
5. Run Disk Utility. 
6. Replace the DIMMs one at a time and test until all bad DIMMs are replace\
d with  known-good modules.
7. Reset the logic board. Refer to “Resetting the PMU on the Logic Board” in this  chapter.
8. Replace the processor module. Refer to Before Replacing the Processor in this  chapter.
9. Replace the logic board.  
						

							
 
18 -   
Power Mac G4 (Mirror/FW800) Troubleshooting  Symptom Charts 
Error Tones
 
Note:  
 Error tones occur before system software loads. 
Computer beeps once at startup
 
One beep means that no RAM is installed or detected.
1. If no DIMM is present, install a known-good DIMM in the top slot and try again. 
2. Reseat the DIMMs.
3. Replace the DIMMs one at a time and test until all bad DIMMs are replace\
d with  known-good modules.
4. Check that the processor module is properly installed.
5. Replace the processor module. Refer to Before Replacing the Processor in this  chapter.
6. Replace the logic board. 
Computer beeps two times at startup
 
Two beeps mean that incompatible RAM types may be installed. Verify that only DDR266 
SDRAM DIMMs are installed. 
1. Replace the DIMMs one at a time and test until all bad DIMMs are replace\
d with  known-good modules.
2. Check that the processor module is properly installed.
3. Replace the processor module. Refer to Before Replacing the Processor in this  chapter.
4. Replace the logic board. 
Computer beeps three times at startup
 
Three beeps mean that no RAM banks passed memory testing.
1. Replace the DIMMs one at a time and test until all bad DIMMs are replace\
d with  known-good modules.
2. Check that the processor module is properly installed.
3. Replace the processor module. Refer to Before Replacing the Processor in this  chapter.
4. Replace the logic board. 
Computer beeps four or  five times at startup
 
Four or  five beeps mean that the ROM is probably bad and cannot be  fixed.  
						

							
 
Power Mac G4 (Mirror/FW800) Troubleshooting -   
19  
 Symptom Charts 1. Replace the processor module. Refer to Before Replacing the Processor in this 
chapter.
2. Replace the logic board.
Video
Screen is black, but startup chime is present, drive operates, fan is running, 
and power LED is lit
1. Check video cable/card connections and connector pins.
2. Test with a known-good monitor. Replace the monitor, if necessary.
3. Remove all third-party devices.
4. Reseat the video card.
5. Clear parameter RAM. Hold down Command-Option-P-R during startup until you hear  a second startup chime.
6. Reset the logic board. Refer to “Resetting the PMU on the Logic Board” in this  chapter.
7. Replace the video card.
8. Replace the logic board.
Screen is black, there is no startup chime, and drive does not operate, but fan 
is running and power LED is lit
1. Check video cable/card connections and connector pins. 
2. Reset the logic board:
3. Refer to “Resetting the PMU on the Logic Board” in this chapter.
4. Reseat the video card.
5. Reseat the processor module.
6. Replace the processor module. Refer to Before Replacing the Processor in this  chapter.
7. Replace the logic board.
Startup chime is present but screen is gray
1. Reset the logic board. Refer to “Resetting the PMU on the Logic Board” in this  chapter.
2. Reseat all PCI cards.
3. Reseat all DIMMs.
4. Test with known-good DIMMs. 
						

							
20 - Power Mac G4 (Mirror/FW800) Troubleshooting
 Symptom Charts
5. If using more than one display, make sure primary display is connected to video card.
6. Reseat the processor module.
7. Replace the processor module. Refer to Before Replacing the Processor in this 
chapter.
8. Replace the logic board. 
Video is distorted
1. Make sure that the video card driver and  firmware are updated to the most recent 
versions.
2. Refer to the adjustments section of the service manual or owner’s manual for the  monitor. Adjust monitor as necessary.
3. Third-party monitors: Try a known-good monitor.
4. Reseat the video cable.
5. Reseat the video card.
6. Check the video adapter, if present. 
7. Replace the video card.
Screen jitters
1. Verify there are no environmental factors causing jitter. Note:  The jitter may be caused by interference from a nearby power line, a 
fluorescent light, or an external device—for example, a radio, microw\
ave oven, or 
another computer. Try relocating nearby electrical devices or moving the\
 computer 
and display.
2. Check all cable connections.
3. Make sure that the video card driver and  firmware are updated to the most recent 
versions.
4. Test with a known-good monitor. Refer to the appropriate monitor manual to  troubleshoot a defective monitor. Replace the monitor, if necessary.
5. Reseat the video card.
6. Replace the video card.
7. Replace the logic board.
Power Mac G4 (Mirrored Drive Doors) computer with ATI Radeon 9000 Pro 
graphics card installed has dif ficulty waking from sleep.
Note:  This issue occurs when one of the following is connected to the video cards DVI 
port:
• a monitor with a DVI-style connector 
						

							
Power Mac G4 (Mirror/FW800) Troubleshooting - 21
 Symptom Charts • a VGA monitor using a DVI-to-VGA adapter
• a DVI-to-VGA adapter that does not have a monitor connected to it
Update to the latest version of Mac OS X. To download and install an update via the 
automatic Software Update feature in Mac OS X, choose System Preferences from the 
Apple menu, choose Software Update from the View menu, then click Check Now. Any 
available updates will be listed in Software Update. 
Sound
No sound from computer’s internal speaker
1. Disconnect any microphones or external speakers.
2. Verify the volume is set appropriately in the Sound system preference or Sound 
control panel and mute is not checked. 
3. Clear parameter RAM. Hold down Command-Option-P-R during startup until you hear  a second startup chime. 
4. Verify the speaker cable is plugged into the logic board.
5. Plug headphones into the headphone jack. If you dont get sound via the headphone  jack, try connecting external speakers to the audio line-out port on the back panel. If 
you still dont get sound, replace the logic board.
6. If you get sound from the headphones, but dont get sound when they are removed,  disconnect the front panel board cable from the logic board, and test again. If the 
internal speaker functions normally, inspect the front panel board cable and replace it 
if necessary. Otherwise, replace the front panel board.
7.  If you get sound from the headphones, the audio line-out port, and the Apple Pro  Speaker jack on the back panel, but you still do not get sound from the internal 
speaker when the front panel board is disconnected, then the audio line-out j\
ack or 
the Apple Pro Speaker jack may be jammed, making the computer act like you have 
speakers connected when you do not. Try inserting/removing the connector from the 
respective jacks several times to see if this makes a difference; otherwise replace the 
logic board.
No sound from Apple Pro Speakers
1. Push on the Apple Pro Speaker jack to make sure it is  firmly inserted into the Apple 
Speaker sound output port. (The Apple Pro Speaker jack has two detents. You should 
feel them as you push the jack into the sound output port. Giving the jack a slight twist 
while inserting it into the port may make a better connection.)
2. Verify the speaker volume and balance are set appropriately in the Sound system  preference or Sound control panel and mute is not checked.
3. Clear parameter RAM. Hold down Command-Option-P-R during startup until you hear  
						

							
22 - Power Mac G4 (Mirror/FW800) Troubleshooting
 Symptom Charts
a second startup chime.
4. Reinstall system software.
5. Replace the Apple Pro Speakers.
6. Replace logic board. 
						

							
Power Mac G4 (Mirror/FW800) Troubleshooting - 23
 Symptom Charts
Fan interference heard through headphones
1. Plug headphones directly to the sound output port on the front of the computer.
2. Connect all other audio devices to the sound output port at the rear of the computer.
Note:   If headphones are connected through audio devices, such as grounded speakers, 
or mixers, and these devices are connected to the headphone sound output port, you may 
hear fan interference through the headphones.
Clicking or clunking type noise heard from Power Mac G4 (Mirrored Drive 
Doors) computer
This noise is due to the fan blades hitting the gasket that surrounds the air intake 
openings.
1. Check that the noise is coming from the power supply fans by brie fly disconnecting the 
processor fan and optical bay fan.
Important:   Do not close the door and operate the computer with these fans 
disconnected.
2. If the noise is coming from the fans, replace the power supply. Note:   Service stock does not contain any power supplies with this issue.
Related Knowledge Base article: 86128 Power Mac G4 (Mirrored Drive Doo\
rs): 
Processor Fan Spins Constantly at High Speed
High noise level with Power Mac G4 (Mirrored Drive Doors) computer
Note:  The sound generated by the Power Mac G4 (Mirrored Drive Doors) computer is 
approximately the same as previous dual processor computers. Customers who upgrade 
from earlier, single processor computers might notice that the computer is louder. This is 
because there are more parts to cool—multiple processors and additional expansion 
capabilities—within the same form factor. However, there are some situations that may 
lead to increased sound levels beyond what is expected.
One is addressed with the 4.4.8 version of the  firmware (BootROM) for the computer. 
Refer to the software download Knowledge Base article 120171 Power Mac G4 Firmware 
Update: Information and Download if the customer has an earlier version. You can tell 
which version of  firmware the computer has by using Apple System Pro filer.
Other situations include the processor fan constantly spinning at high speed, and a 
clicking sound that comes from the computers power supply. If that is the case, refer to 
those symptoms in the Startup and Sound sections, respectively, in this chapter. 
						

							
24 - Power Mac G4 (Mirror/FW800) Troubleshooting
 Symptom Charts
Hard Drive
Single internal ATA drive does not spin; flashing question mark on screen
1. Check all cable connections to the hard drive.
2. Try another power connector on the power cable harness. If the power cable is 
defective, replace the power supply.
3. Replace the hard drive. If the problem is resolved, make sure the driver and system  software are updated to the most recent versions.
No internal SCSI drive icon appears on the desktop 
1. Check that the drive is listed in Apple System Pro filer. If it is, go to step 2. If it is not, go 
to step 5.
2. Update the drivers.
3. Verify there are no duplicate SCSI device addresses on a single SCSI bus. 
4. Disconnect external SCSI devices and check for proper termination. 
5. Reseat the SCSI PCI card and verify the cable is seated  firmly in the card and drives.
6. Check internal SCSI termination. Internal drives should not be terminated; the SCSI  cable should have termination at the end.
7. If more than one SCSI device is on the SCSI chain, remove one device at a time and  retest. Replace the bad drive.
8. Replace the internal SCSI data cable. For the Power Mac G4 (FW 800) model, this is  a third-party cable that is not available from Apple.
9. Replace the SCSI PCI card. For the Power Mac G4 (FW 800) model, this is a third- party card that is not available from Apple.
10. Verify SCSI drive power by testing different power connector or using a volt meter to  check for 12 V/5 V. 
						

							
Power Mac G4 (Mirror/FW800) Troubleshooting - 25
 Symptom Charts
No external SCSI drive icon appears on the desktop
1. Verify there are no duplicate SCSI device addresses.
2. Verify the total cable length does not exceed the maximum total cable length for the 
SCSI card. See Knowledge Base article 58204.
3. Reseat the SCSI cable going to the SCSI card.
4. Replace the terminator on the external SCSI device.
5. Reseat the SCSI card.
6. Replace the SCSI card. For the Power Mac G4 (FW 800) model, this is a third-party  card that is not available from Apple.
7. Replace the SCSI drive cables one at a time. For the Power Mac G4 (FW 800) model,  this is a third-party cable that is not available from Apple.
8. Disconnect the external SCSI chain. Using known-good cables, reattach devices one  at a time.
Hard drives connected to ATA-100 bus are not recognized
1. Check all cable connections to the hard drive.
2. Try another power connector on the power cable harness. If the power connector is defective, replace the power supply.
3. Verify that you are booting with the discs that shipped with the unit, or are known  compatible with the unit. Note that booting with an incompatible version of the OS may 
mean that the necessary drivers to recognize the ATA-100 bus are not installed, and 
therefore any devices connected to that bus will not be recognized.
4. Test the hard drive on the ATA-66 bus. If it is recognized properly, double-check your  media to verify that it is proper for this unit. If the media is correct, visually inspect the 
ATAPI cable on the ATA-100 bus for damage, and test with a different cable. If the 
other cable allows the drive to function correctly, order a replacement cable.
5. If the hard drive does not function on the ATA-66 bus, replace the hard drive. If the  problem is resolved, make sure the driver and system software are updated to the 
most recent versions.
6. Replace the logic board. 
						

							
26 - Power Mac G4 (Mirror/FW800) Troubleshooting
 Symptom Charts
Optical Drive
Optical drive tray won’t open 
1. Before opening the computer, try the following:
Note:  When following the steps below make sure that there is power to the com\
puter 
and to the Apple Pro Keyboard and Apple Pro Mouse. 
If in Mac OS 9.2,
• Press the Eject key on Apple Pro Keyboard.
• To open the second optical drive on a Power Mac G4 (Mirrored Drive Door\
s)  computer, press Option-Eject on the Apple Pro Keyboard.
• Open the Eject application found in the Eject Extras folder. The Eject E\
xtras folder  is located in the Apple Extras folder on the CD.
• Click the iTunes eject button, shown below.
• Hold down the mouse button when you hear the startup sound as the comput\
er  restarts.
• Start up from Mac OS X and customize the toolbar with an eject button.
If in Mac OS X,
• In the Finder, Choose View > Customize Toolbar. In the window that appea\
rs, drag  the Eject button to the toolbar, then click Done. Select the disc you wa\
nt to eject in 
the Finder window, then click the Eject button in the toolbar.
• Press the Eject key on the Apple Pro Keyboard.
• To open the second optical drive on a Power Mac G4 (Mirrored Drive Door\
s)  computer, press Option-Eject on the Apple Pro Keyboard.
• If you have a keyboard without an eject key, press F12 (under Mac OS X \
10.1 and  later). Note: You must press the F12 key longer to prevent the tray fro\
m 
accidentally opening.
• Click the eject button in iTunes (shown above).
• Hold down the mouse button when you hear the startup sound as the comput\
er  restarts.
• Start up from Mac OS 9.2 and follow the options in the section above.
If the computer is not responding,
• Restart the computer and hold down the mouse button when you hear the st\
artup  sound.
• Restart the computer, hold down the Option key, and use the startup mana\
ger to