This cable brought a dead computer back to life
A client gave me a mid-2012 MacBook Pro for recycling after he'd replaced it. The computer rarely would boot at all. It wasn't the hard drive.
I kept the computer around, loathe to recycle something that seemed close to working.
I had bought the new part to see if it improved another client's computer after a hard drive change, but it made no difference on that machine.
Swapping the cable was easy; the toughest part was pulling the sticky part off the case. (I didn't want to damage the existing cable.
Voila...now the computer is perfectly healthy. After repairing dozens of Macs, I had no idea the cable could be an issue---till I found mention of it on an online forum.
I didn't bother to stick the new cable to the case.