Chosen Solution

This Mac was dropped, (not by me) and and now when trying to boot, it gets past the spinning wheel, and just as the Mac with the progress bar comes up in blanks. I’ve removed the hard drive and checked that it’s OK. It mounts an another Mac, and is readable. The same thing happens when trying to boot from the Mac DVD. So I don’t think it’s the hard drive. Removed and reseated the RAM, no change. No warning beeps at start up. Could the logic board have been damaged? How can I tell what part to replace?

Hi, i believe i may have a solution for you. I had the exact same issue with my 15" Unibody MBP (Late 2008). I tried EVERYTHING I found online, and I mean everything to no avail. Resetting pram, nvram, smu, deleting system files, re-installing snow leopard, safe boot, different hard drive, etc. Etc. Nothing worked. I had given up, as I simply couldn’t find anything else on the web that I hadn’t tried already. Then it hit me, if the screen is fully lit up, everything is working perfect UNTIL it logs into and immediately goes to sleep, AND won’t wake from sleep, then it’s probably one isolated problem with sleep functionality alone. And it was. :)

  1. open the mbp up and look at the logic board
  2. look at the IR/Sleep ribbon cable. (Use iFixit reference guide, here’s the image
  3. Make sure it’s plugged in ALL the way. (mine was very loose, nearly unplugged completely)
  4. Once the cable is in place, simply reboot :) This fixed it, so far, seems permanent! Let me know if it works for you.

Leave it boot up to 10 minutes… This gray progress bar resembles a Safe Mode startup, or an EFI firmware installation or restoration; however this issue is not related to firmware. There’ isn’t supposed to be a progress bar, If this happens each time your Mac starts up, it probably indicates Mac OS X v10.6 is attempting to diagnose and resolve an issue with your hard disk or the data on it. Let it boot, or try a safe (shift) boot and run Applications->Utilities->Disk Utility->Disk First Aid tab: repair disk, and repair permissions. If this answer is acceptable please return and mark it. Good Luck, N.