Did it - Juhu

crwdns2853023:0crwdne2853023:0

Since a view month the upper part of my iMac-Display (mid 2007) was darker than the lower part. Also the the contrast on the complete display was bad. (see first picture)

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After the first try, I didn't have the problem on the upper half but on the lower part (changed both, upper and lower CCFLs, second picture). So the next day I opened up everything again and found that I had torn off one of those thin cables soldered to the CCFL during reassembling.

Now the display works as on the first day again. (third picture)

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After removing the black surround (step 21) DO NOT remove those transparent sheets from the backlight-reflector. So you won't need to clean them before reassemble. Just pull out the CCFL tubes.

During reassembling after putting the LCD back onto the backlight-reflector, be sure to clean off the dust from the top sheet with a soft tissue.