For $29/mo, we provide access to advanced level technicians who will answer your questions on any Macbook board related matter to the best of their knowledge promptly & walk you through how to solve your problem so you can deliver a working board to your customer.
Should mention that the system boots normally, but after about 5 minutes the fans go on high and then about 10 minutes later the screen will go solid grey (no image). If left alone the display returns and the process repeats. The system never shuts off or reboots.
Turns out this was due to some sort of "crust" on the board in the area of the camera connection to the Logicboard. I've seen this a couple of other times on iMacs where it looks like liquid damage but extremely light AND in an area that there's no way liquid could have gotten only there. Very strange but a light surface cleaning resolved the issue and it now passed ASD with flying colors.