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MacBook Pro 13" locks when bottom cover is inst...

Hello All!

I've been repairing and building computers for over 15 years and I have a real head scratcher here.  I've done search after search and can't find a solution to this issue.

I'll give you the rundown on everything I've done....

I have a MacBook Pro 13" that had a loose screen, so I took the screen off and tightened the hinges.  After I'm done I put everything back together in is place and hit the power button, I get a ding, an Apple and a spinning thingy. (technical term)

From here sometimes it will lock right there and sometime it will boot but extremely slow, then will lock after using it for a few minutes. 

When this happens the cooling fan sounds like it wants to fly right out of the case and the bottom gets HOT!

So I take the computer apart again and look around thinking that I may have missed a wire or something, everything looks perfect on the inside.

So I re-seat the memory and set the bottom back on the laptop (without screwing it down) and hit the power button, and it WORKS!

After what I thought was a good fix I screw the bottom back on the computer and hit the power button, and it locks again, I reboot several times and still the same thing.

I took the case back off again and looked around, nothing wrong, I screw the bottom cover back on again and I get locking issues.

From here I take the bottom off again and replace the hard drive and memory, turn it over on my rubber pad (without installing the bottom cover) and it boots flawlessly.  I screw the cover back on and it locks during boot, again the fan starts running higher and higher until the computer turns itself off.

So now I unscrew the cover, but leave it installed and boot the machine, it boots and I start using it, after about 5 minutes the mouse starts getting jittery and the fan starts ramping up, with the computer still on I lift it up allowing the bottom cover to fall away, immediately after doing this the fan goes back to normal and the computer works normally.

So the end of the story is that I have a macbook that only works when the bottom cover isn't installed.  I'm tearing my hair out trying to figure this one out.  I'm almost thinking that the aluminum cover is touching something and shorting it out but I can't see what it could be, I reinstalled all the parts back where I had them to begin with.

Any help would be greatly appreciated.

2 problems, the fan isnt seated right and the bottom cover is squashing it when on

secondly, if it ONLY boots up with the bottom cover off, then the SATA cable is kinked and being disconnected or a feed there in of the 24 pins (as i recall) in the feeder cable of the SATA flexicable from logic to hard drive.

The computer will sometimes boot with the bottom screwed on, if it does boot it boots VERY slow. 

I took a look at all the cables and reseated them, no kinks of any kind, still having the issue.

Is it possible to place some kind of spacer on the logic board to keep the cover away from it?

Theres no way the logic board itself should be contacting or even close to the cover when closed.

the only thing touching same when closed is the fan, battery and hard drive.

I used to repair a lot of laptops like yourself.

The only imaginable thing causing a slow boot with the cover on is the HD is being squashed ever so slightly (Ive only ever heard of this happening,....once)

The HD cover is incredibly touchy, if fact if you dont even put a HD cover back on without a torque wrench, youre guaranteed it will NOT spin up properly.

I can only imagine excess pressure on the HD,  ....so youre sure the HD is seated ok?

I guess I should have mentioned this little tidbit earlier but the hard drive is an SSD so no moving parts to squash.

One of the really weird things is that I don't even have to press on the cover to get it down, I can lay it on there and it fits into the groove with no problems. When it put the screws in its only very lightly, not torquing on the bottom cover at all.

I triple checked the memory and hard drive, everything is seated and connected correctly.

Did you make sure to install the screws in the correct postions.  Some are longer than others and could be causing a short to the case if incorrectly installed.

Sure did. The 3 long ones went into the back where they were supposed to go and the 7 others that are all the same length went in the remaining holes.

there are ONLY 2 possibilities of the bottom cover affecting the Mac

put the bottom cover on WITHOUT the screws just held in place with 2 pieces of tape.  Turn it on, test it

Do the same WITH the screws in place........test again.

If its acting up with the cover on without screws, then theres a pressure fault where the cover is contacting the fan or SSD or battery and thereby pressing against X. Its nearly impossible for there to be any kind of electrical contact this way.

if it does it ONLY with the screws in, then the screws are causing a torque in the logic board or cable somewhere and/or causing a contact somewhere as the cover is pulling against its fastening points via the screws.

Id give $20 to see this chain of causation in action.

Did you ever figure this out? I am having the same problem.  I have reset the logic board, RAM, I have taped the underside of the cover in case this was somehow shorting something.  It is driving me crazy!  Cover off, the computer runs fine.  Cover on the fan blows, computer gets slow - if it loads at all.  I lose my wireless, and date settings.  This is a macbook pro 2010, I have replaced the logic board on this computer with another 2010 A1278 logic board (and done this many times before.).  Any help would be appreciated

Just to follow up on an old thread with a possible solution;

I had the same problem. My Macbook Pro (13" mid 2012) suddenly became very slow just by moving the cursor. Tried everything I could think of.

SMC reset

NVRAM/PRAM reset

Repair disk permissions

Repair HDD

Tried safe booting

Did Apple hardware test

Tried another HDD

Tried different RAM

Nothing worked. My first thought was that it was the logic board. I decided to send it in for repair at an Apple Authorised Service Provider (we don't have Apple Stores in Denmark). My Macbook is still under warranty. They changed the HDD cabel/connector, and for now my Macbook is working like it used to do (3 days as of now).

So if nothing else works, the cable could be the cause.

I just had this happen to my mid 2012 Macbook Pro 13.3 inch dual core i5 2.5ghz.

I have also found the solution! I've had my laptop for 3 years and 1 year ago I installed 16gb of ram and removed the superdrive to replace it

with a 1tb data III hard-drive. I bought a special mounting bracket that fit in the superdrive slot so the hard-drive wouldn't move around. When

you install it you have to disassemble a good chuck of the laptop in order to get all the screws tightened up. When you flip the MBP over in the top left,

over by the superdrive I believe is the sound bar which was the cause of my problems. When I reinstalled the sound bar one of the wires wasn't seated completely but it was really hard to tell. Never gave me a problem until now. What happened is the wire had been squished by the case and gradually deteriorated exposing a tiny bit of the bare wire. Over by that area where the bottom is seated there is a metal pad that makes a connection for ground for part of the computer. The pad was shorting out the computer when the bottom was screwed on but when it was held in place by tape or off it didn't make enough of a connection to disrupt the computer. After unscrewing the sound bar and tucking the wire further into the computer, the lid could be screwed down tightly again without this problem. The problem was very hard to see because it looks like it will clear the lid, but it won't. Hope this helps.

I had the same issue and I've removed the superdrive, soundbar and antenna coax cables and reinstalled with care making sure wires won't touch under pressure. In my case macbook was running either the bottom cover was installed without screws or not installed at all. When bottom cover was installed with screws it shuts itself down as soon as I turn the device on. it's was really annoying to figure this issue out since it was a weird one that thought me how much the device is sensitive.

最後更新：2017-08-29 18:04:35

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