Apple MD094LL/A manual L04, Service Display Utility to, Issue resolved. If video card

6.	Verify if issue is still present	Yes	Go to step 7
	with replacement logic board
		No	Issue resolved.
	installed.
7.	Reinstall original logic board	Yes	Replace LCD panel. Run Apple	L04
	and verify if issue is still present		Service Display Utility to
	with original logic board		verify the resolution of issue.
	reinstalled.		Enter the resulting verification
			code into the “Notes” field
			of GSX and return system to
			customer if repair is complete.
		No	Issue resolved. If video card
			was replaced, reinstall original
			video card.

2010-09-09 iMac (27-inch, Mid 2010) Symptom Charts — Display  67