Apple imac 20 inch early 2008 User Manual

iMac (20-inch Early 2008) 261
IR Sensor/Receiver
Supported applications do not respond to input from the remote control
Perform the checks above under “IR Remote” to verify that the Apple Remote is functioning 1. 
correctly, and retest. Do supported applications now respond to input from the IR remote? 
Yes: Problem resolved. 
No: Go to the next step.
Verify that the IR Sensor can be seen in the Apple System Profiler. Open the Apple System 2.  
Profiler and click on the “USB” section. You should see the...

iMac (20-inch Early 2008)  — Symptom Charts  262
Built-in iSight Camera
The built-in camera is not recognized
Boot the 1. computer to the desktop and launch iChat AV. Note: You do not need to be 
connected to a network to use iChat AV to troubleshoot. Verify that the correct versions of 
Mac OS X and iChat AV are installed. Reinstall or update software as needed. 
Open the iChat AV preferences and click on the ‘Video’ icon. Verify whether the camera is 2.  
recognized by the iChat AV software. Is the...

iMac (20-inch Early 2008)  — Symptom Charts  263
quality acceptable? 
  Ye s: The camera is functioning normally. The image quality problems may be caused by 
bandwidth limitations when using iChat over the internet. Instruct the customer to use the 
iChat AV connection doctor feature to verify that there is sufficient bandwidth to have a 
video iChat session without a significant degradation of image quality. 
 
No:  The camera may not be functioning normally. Replace the front bezel for poor image...

iMac (20-inch Early 2008)  — Symptom Charts  264
Speakers
Can’t hear sound from the speakers
Disconnect any external microphones, speakers, or headphones. 1. 
Access System Preferences and select Sound. In the Sound pane, select Output and make 2.  
sure the Internal speakers are selected as the device for sound output, the Output volume is 
adequate, and Mute is not selected.  Do you have sound now? 
Yes: Problem resolved. 
No: Go to the next step.  
Reset parameter RAM. Press Command-Option-P-R during...

iMac (20-inch Early 2008)  — Symptom Charts  265
Mouse (also see Wireless Issues topic)
The scroll bar on my mouse does not work in all directions
See Knowledge Base article 302417, for instructions and a QuickTime movie demonstration on 
how to clean the scroll ball. 
My mouse doesn’t work at all
Turn over the mouse and check the if the red LED on the underside of the mouse. Is the LED 1. 
lit? 
 
Yes: The mouse has power. Try using the mouse on another surface. Non-reflective, opaque 
surfaces without...

iMac (20-inch Early 2008)  — Symptom Charts  266
Mouse tracking issues
f your Mighty Mouse is covered in fingerprints or its surface has become soiled, it can be gently 
wiped with a clean lint-free cloth. If necessary, moisten the cloth using only water, making sure 
not to oversaturate it. Be aware that the mouse contains electronic components that may be 
damaged if water drips from the cloth into the mouse via the seam around the scroll ball or 
around its underside.
The same procedure can be used to...

iMac (20-inch Early 2008)  — Symptom Charts  267
No: Replace the logic board.
My keys are sticky or slow to respond
Try a known good keyboard.1. 
Open System Preferences. Click on the keyboard and mouse icon. Adjust the “key repeat 2.  
speed and delay until repeat” rate.
Replace the keyboard.3. 
When I type, strange characters appear on the screen
Depending on your iMac’s settings, a simple keystroke can change your keyboard from 1. 
English to Japanese. This can result in some pretty funny characters...

iMac (20-inch Early 2008)  — Symptom Charts  268
Wireless Issues (also see Additional Wireless Topics)
The aluminum Apple Wireless Keyboard will not turn on.
Confirm that the batteries are installed properly and the batteries are known good.1. 
Open the battery compartment over. Make sure to install the positive and negative ends of 2.  
the batteries in the keyboard as shown. The keyboard will not turn on if the batteries are 
incorrectly installed.
Replace the battery compartment cover.3. 
Turn on the...

iMac (20-inch Early 2008)  — Symptom Charts  269
Can not set up the aluminum Apple Wireless Keyboard
Confirm that you have Mac OS X v10.4.10 or later installed and install the keyboard software 1. 
update. If using Mac OS X 10.4.5 or later the keyboard software update is not needed.
Install the batteries. Use a coin to remove the battery compartment cover.2.  
Slide the batteries into the battery compartment as shown below. Replace the battery 3. 
compartment cover and leave the keyboard turned off.
Open...

iMac (20-inch Early 2008)  — Symptom Charts  270
Assistant on the Apple Wireless Keyboard. Press the Return key on the keyboard when you 
are finished.
Once the assistant says the computer and keyboard have successfully paired, click Continue.11 . 
Setup is complete. Click Quit.12.  
The LED is flashing on the keyboard or mouse
When your Apple Bluetooth mouse or keyboard is turned on, the light flashes twice in 
succession, and then repeats, (blink-blink-pause, blink-blink-pause). This means the keyboard...