Apple MD094LL/A Manual Do Utilizador

iMac (27-inch, Mid 2010) Symptom Charts — Display 

 2010-09-09

3.  When display flicker, verify 

whether one of the following 

symptoms occurred:

•  Flickering image
•  Horizontal bands of static 

intermittently appear

•  Dock and / or menu bar shift 

positions

•  Display intermittently flashes 

on / off

Yes

Remove glass and LCD panel. 

Check , reseat, and secure the 

DisplayPort LCD cable to both  

ends. Check and reseat the 

VSync cable to both ends. 

Go to step 4.

No

LCD panel OK.  

Go to step 4.

4.  Power ON computer and verify 

if issue still occurs.

Yes

If connections are secure and 

display is still flickering, go to 

step 5.

No

Issue resolved. 

5.  Carefully disconnect and 

verifiy if any of the four cables 

on back of LCD panel show 

signs of damage, corrosion, or 

pinched wires.

Yes

Replace and damaged 

cable(s) and retest.

No

Go to step 6.

6.  Verify whether flickering occurs 

when brightness level is set 

below max.

Yes

Image present but backlight 

is flickering. Replace Vertical 

sync cable (between LCD 

panel and LED Backlight 

board) and retest. Replace 

backlight board if problem 

persist.

No

Replace internal DisplayPort 

cable (between Logic Board 

and LCD panel), retest and go 

to step 7.

7.  Verify if flickering issue is still 

present.

Yes

Replace LCD panel.  

Run 

 to verify the resolution 

of issue.  

Enter the resulting verification 

code into the “Notes” field 

of GSX and return system to 

customer if repair is complete

No

Issue resolved.