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View Full Version : MacBook Pro Won't Boot (Or Will but only slightly)



nibbles
5th April 2013, 07:55 PM
I got given a MacBook Pro by a mate who had taken it to a repairer (not sure who but I don't think they were an authorised Apple repairer) and they'd given up trying to fix it so he bought a new one.

Anyway, it's a late 2011 13" MacBook Pro that refuses to boot. If I disconnect and reconnect the battery it'll spin the fans up and get to the Apple logo & spinner, after about 30 seconds it just shuts off and pressing the power button won't start it, the process must be repeated to make it start again.

I'm wondering what diagnostics I can try to revive this thing? I've tried an SMC reset, the DC-in board was replaced and I've swapped the RAM configuration around. To me it seems like a firmware issue(?), any other ideas?

Byrd
5th April 2013, 10:14 PM
Interesting fault - what happens with disconnecting the battery, and starting it up off mains - same issue? I'd disconnect non-essential things like HD, just have a single stick of RAM, no battery. I'd also (gingerly) apply pressure to various points of the motherboard (wear some rubber kitchen gloves, and apply firm pressure around parts such as around DC board to motherboard connector, around RAM slots, video cable, GPU) to see if there exists any loose connections. Yes, this sounds a bit crazy, but I've come across several Mac and non-Mac laptop motherboards that have fired up with this sort of coaxing. :D

If it was a corrupt firmware you would get no life at all.

h4ck
5th April 2013, 11:50 PM
don't press around on the logic board. you handle PCBs by the edges, and that's it.



Interesting fault - what happens with disconnecting the battery, and starting it up off mains - same issue? I'd disconnect non-essential things like HD, just have a single stick of RAM, no battery. I'd also (gingerly) apply pressure to various points of the motherboard (wear some rubber kitchen gloves, and apply firm pressure around parts such as around DC board to motherboard connector, around RAM slots, video cable, GPU) to see if there exists any loose connections. Yes, this sounds a bit crazy, but I've come across several Mac and non-Mac laptop motherboards that have fired up with this sort of coaxing. :D

If it was a corrupt firmware you would get no life at all.

h4ck
6th April 2013, 12:39 AM
you have two points that i'd look at here.

the first is the boot volume. do you have an external drive that you can boot from? try that. you may want to remove the internal hard drive.
if you replace the drive, and/or boot from an external drive and it boots right up, you've solved the spinning gear problem.

Apple Logo = found system volume, spinning gear = loading system. why it's shutting off like that, is to be determined.. could be kernel panicking on boot. is it running at LEAST 10.6.6?

you can also try holding command+V when booting it up, that will show the verbose boot screen and give you a little insight to where the failure might be.

if it's not as simple as a hard drive, it sounds likely that it's a logic board problem that is not user-serviceable. I'd contact apple au and inquire about depot service (flat rate repair) - it runs about 350USD here, not sure what the fee is in australia..i haven't lived there in years.

nibbles
6th April 2013, 06:53 AM
I should add that it had no hard drive in it, I had one in a USB case that I put in there. It is running 10.8 Server. I doubt booting via USB will make a difference.

As soon as I saw it I feared the logic board but I want to try a few other things before calling it quits, I was originally told it had a broken screen which I was hoping it did because I was just going to remove it and use it as an HTPC. :(

I've got some electronics cleaner around, might smother it in that, wouldn't be the first time it's fixed dodgy circuit boards.

This particular model ran with 1333MHz RAM? I've got some spare 1066MHz lying around, will using slower ram still work?

nibbles
6th April 2013, 08:45 AM
I've been playing with it for the past half hour - battery disconnected. It'll run for 58 seconds with a normal starting procedure, Just as it changes to the login screen/ solid apple logo and no spinner it completely shuts off. I tried the lion Internet recovery startup, it downloads and then the same things happens, just as it finishes loading it shuts off.

nibbles
6th April 2013, 10:45 AM
IT LIVES!!! After a good old fashioned tinker and clean with electronics contact cleaner and a toothbrush it lives. Sort of. I've still got to work out a few small issues like the keyboard not working in the OS but working in the boot device screen, etc. So a pretty good score if you ask me. :)

Thingme
6th April 2013, 11:51 AM
Sounds like someone spilt something in it. Look for corrosion.

Geez I did just that the other day to my Retina MBP. I knocked over a glass of cabernet sauvignon and the keyboard and innards got a good sprinkling of the red stuff. Fortunately, after an inverted shake and wipedown, it still works. Whew!

nibbles
6th April 2013, 01:23 PM
There weren't any signs of liquid damage, just a couple of areas with dust (presumably some of that dust was metallic enough to conduct electricity).

All good now apart from the keyboard ribbon cable which I ever so slightly damaged, it has separated slightly on the corner causing the computer to think the power button is pressed and turn it off. At the moment I've started it up, quickly disconnected the keyboard and connected an external one.