Apple imac 21 5 inch late 2009 User Manual

iMac (21.5-inch, Late 2009) Symptom Charts — Startup and Power 41 2010-11-18
Burnt Smell/Odor
Unlikely cause: speakers, microphone, rear housing
Quick Check
SymptomsQuick Check
Burnt Smell/Odor
•  Burning smell
•  Unusual odor
1.  Verify that computer is the source of the odor.
2.  If system is new, see kBase #TA22044: New 
Equipment: Odors May Be Present Short-Term.
3.   Disconnect all third-party devices and check to 
see if any external device is the source of odor.
4.  Inspect air intake and air...

iMac (21.5-inch, Late 2009) Symptom Charts — Startup and Power 42 2010-11-18
3.  Verify if source of odor can be 
located using your nose. Yes
Replace affected module(s) 
and retest system. P08
No Contact Apple for assistance 
if you feel that there is a 
possible safety issue with 
computer that has not been 
resolved in previous steps.
Uncategorized Symptoms
Quick Check
Symptoms Quick Check
Uncategorized Symptoms
•  Unable to locate appropriate 
symptom code.
1.  Make sure system is plugged into a...

iMac (21.5-inch, Late 2009) Symptom Charts — Display 43 2010-11-18
Display
Backlight Issue/No Backlight
Unlikely cause: hard drive, optical drive, speakers, camera, microphone
Quick Check
SymptomsQuick Check
Backlight Issue/No Backlight
•  No image
•  Partial backlight failure
•  Backlight flickers
•  Display dim
1.  Check for Software Update.
2.  Verify that System Preferences > Displays > 
Brightness control setting is above minimum.
3.   If no image on built-in display, connect external 
display to...

iMac (21.5-inch, Late 2009) Symptom Charts — Display 44 2010-11-18
5.  Shine bright (low heat) 
flashlight onto front of LCD. 
With computer powered ON 
verify if a faint image is visible. Yes
LCD panel functional but 
backlight is missing or 
dim. Remove LCD panel 
and inspect and reseat the 
following cable connections:
-Output cable between lower 
end of LED backlight board 
and lower end of LCD panel.
-Vertical sync cable between 
upper end of LED backlight 
board and LCD panel.
-DC power cable...

iMac (21.5-inch, Late 2009) Symptom Charts — Display 45 2010-11-18
Noise / Unstable Flickering
Unlikely cause: camera, microphone
Quick Check
SymptomsQuick Check
Noise / Unstable Flickering
•  Unstable image
•  Flickering image
•  Humming noise from display
•  High frequency noise from 
display 1.
  Verify that intake vent on bottom of computer is 
not obstructed.
2.  Inspect system for third party software that is 
being used to set fan speeds to a higher than 
normal RPM. Some users may install this...

iMac (21.5-inch, Late 2009) Symptom Charts — Display 46 2010-11-18
5.  Shine bright (low heat) 
flashlight into front of LCD. 
Verify if an image is being 
displayed when flickering issue 
is occurring. Yes
Image present but backlight 
is flickering. Replace vertical 
sync cable (between LCD 
panel and upper end of LED 
backlight board) and retest.
If issue persists, replace LED 
backlight board. X03
M04
No Replace LVDS cable between 
LCD panel and logic board, 
and retest. X03
6.  Verify if noise varies...

iMac (21.5-inch, Late 2009) Symptom Charts — Display 47 2010-11-18
LCD Image Issues
Unlikely cause: power supply, hard drive, optical drive, fans, speakers, camera, microphone
Quick Check
SymptomQuick Check
LCD Issues
•  Incorrect/missing colors
•  Distorted/blurred image
•  Pixel anomalies
•  Vertical/horizontal lines
•  Non-uniform brightness 1.
  Allow display to reach normal operating 
temperature for about 15 minutes before 
evaluating front-of-screen performance.
2.  Check display preferences for...

iMac (21.5-inch, Late 2009) Symptom Charts — Display 48 2010-11-18
Incorrect/Missing Colors
Unlikely cause: power supply, hard drive, optical drive, fans, speakers, camera, microphone
Quick Check
SymptomsQuick Check
Incorrect/Missing Colors
•  Wrong color display
•  Color/contrast issues 1.
  Allow display to reach normal operating 
temperature for about 15 minutes before 
evaluating front-of-screen performance.
2.  Verify if System Preferences > Display settings are 
configured to use default display...

iMac (21.5-inch, Late 2009) Symptom Charts — Display 49 2010-11-18
Distorted/Blurred Image
Unlikely cause: power supply, hard drive, optical drive, fans, speakers, camera, microphone
Quick Check
SymptomsQuick Check
Distorted/Blurred Image
•  Text and graphics appear fuzzy
•  Image corrupted 1.
  Set System Preferences > Displays to native 
resolution of LCD. Non-native resolutions are 
unable to produce optimal clarity.
2.  Clean outside of glass panel.
3.   Boot from install DVD to determine if a...

iMac (21.5-inch, Late 2009) Symptom Charts — Display 50 2010-11-18
6. Inspect glass panel. Verify if 
issue is caused by condensation 
or contaminants on inside 
surface of glass panel. Yes
Clean glass and/or LCD using 
procedures in Glass Panel 
take-apart chapter.
Identify possible sources 
of contamination (nearby 
cigarette/cooking smoke, 
heavy airborne dust, etc.) 
to prevent recurrence. 
Condensation should 
dissipate after computer has 
been running a few hours.
No Go to step 7.
7.   Remove LVDS...