Chosen Solution
The display is strongly tinted yellow
Please give is the last three figures of your serial number to see if you qualify for a free fix from Apple. Here’s some info on yellow screen issues Apple has had: http://www.macworld.com/article/1146754/…
Their have been a few different causes for Yellow screens within LED back lit LCD units. The first is the reflective foils used in the LED bars get burnt over time causing the back scattered light to be colored in the 24" & 27" models. It took quite a long time for this to be come evident. The second was in the newer 2011 21.5" Apple received a bad run of LCD screens so within a few months the screen became yellow. Sadly both issues require replacing the screen and as far as I know both extended repairs have expired now.
I did not think faulty manufacturing issues could expire? I used to run a Bike Shop and a customer returned a Repco Cycle 30 years old in good condition except the welding on the frame was faulty, a bad batch and all were covered under Australian Consumer Law as Manufacturing Faults were covered for Life? He got a replacement at no expense to himself. I run my Classic 2007 iMac 24” (Windows 10 dual boot El Capitan) a few weeks a year not to overwork it. The last few starts I found the screen had a yellow tinge, I investigated this through Apple Forums and found it was a Manufacture Fault, I am looking for a new screen, found some on eBay from time to time in US. I feel this should be covered under Australian Consumer Law like the 30 year old Repco Cycle.
