Chosen Solution
I was on my way to re-paste the heat sink heat spreader, which was going fine. But, when I put the logic board back in and went to reconnect everything, I discovered I had gotten the flex cable of the battery indicator lights stuck under the board. I took the board off and found that I severed the cable right in the middle. I reconnected everything else, I’m fairly sure correctly, then went to see if it’d work without that. But, nothing happens when I hit the power button. When I plug the charger in I still see the green light on the MagSafe adapter. So will the computer not power on if the battery indicator light cable is severed as I’ve done, or is that not the issue and I’ve caused some other problem? It’s unclear to me whether that circuit is part of the whole SMC and power setup or not. I kinda thought it would function without this but it doesn’t. Otherwise where should I start troubleshooting? The cable in question is in step 15 here MacBook Pro 13" Unibody Mid 2010 Heat Sink Replacement
First here’s the needed part Unibody Macbook Pro 13" Battery Indicator/Sleep board, Apple P/N: 922-9523 (09-12) Yes, the lack of signal from the checker board as the sleep sensor is also part of it! But! You still could have other issues here as well, so you’ll first need to replace the cable to find out.
