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roasted
Dec 2, 2011, 09:41 AM
Hi there. I'm dealing with a problematic Macbook. I believe it's from the 2009 era.

If I press the power button, the power on it immediately dies off. I can hear the fan power down and eventually, silence. I took it apart and scanned the board rather extensively. I couldn't find anything wrong with it whatsoever. I put it back together. After I got it back together, when I pressed the power button, I absent-mindedly kept holding it down. When it started up, I was happy, but I realized it was not fixed as I was able to repeat this process over and over.

Press power button - powers up, shuts off immediately.
Hold power button for 10-15 seconds - powers up and stays consistently running 100%.

I can only assume we're talking about a hardware issue here, but considering we're able to get the system running full bore with no issues *IF* I hold down the power button, I'm beginning to feel lost in regard to isolating what part it could be?

I tried to clear the PRAM but it doesn't seem to respond, as I MUST hold down the power button to boot it, and in doing so it doesn't give me the system powerup sound that Macs normally do. I did pull the battery and hold down the power button originally to drain the charge, but that did nothing.

Any thoughts?



logana
Dec 2, 2011, 11:53 AM
Probably a faulty power-on switch...

A new top case should fix that - is this a unibody MacBook or the earlier model (A1181) - they changed around September/October 2009 ?

roasted
Dec 2, 2011, 01:44 PM
I thought about that, however I was skeptical because the power switch (I would think) is a direct on/off piece of hardware. The hardware turns on... it just doesn't STAY turned on unless the switch stays on. I have another Macbook here of the same era, so I'll swap out the top cases and see what happens.

roasted
Dec 2, 2011, 02:41 PM
Top case made no difference. Same issue with the alternative top case...

So weird. I wonder what it could be?

logana
Dec 2, 2011, 02:47 PM
Try the other top case - it may not be the actual switch - the ribbon cable that connects the top case to the logic board is fairly fragile and may be damaged internally.

Let us know what happens - sounds like the A1181 model since changing the top case on a unibody is a job and a half....

If you look on the logic board near the top case connector you may see a couple of small terminals with PWR between them - the position varies with the processor but normally in the area just below the fan. Short across the terminals with a small screwdriver and that should power-on the board with no top case connected and you can connect a USB keyboard and mouse and see if all is well.

functionchen
Mar 15, 2012, 11:50 PM
I have a macbook 13' model A1342 (unibody) and somebody accidentally got energy drink on it (carbonated) I realize that if i just press the power button it'll turn on and make the apple sound with the sign come on and then it'll shut off by itself and keep trying to turn on until the battery dies. But if i hold down the power button, it will turn on completely and runs perfect. However the internal keyboard won't work. Now I know as long as I hold down the power button with a clamp and use a USB keyboard my computer is fully functional. I was wondering if it's worth the risk to buy a new top case, replace it, and hope that would solve the problem? I'm a broke college student and really don't have any money to spare so the 75 bucks (http://www.ebay.com/itm/OEM-Apple-Macbook-UNIBODY-A1342-MC207-US-QWERTY-Keyboard-w-Top-Case-A-/190649986599?pt=PCA_Mice_Trackballs&hash=item2c639fee27#ht_2384wt_982) i see that they sell on ebay is a lot of money. help!

huntibia
Jun 15, 2012, 05:22 PM
Sorry to bring back an old thread, but I have this problem too and I don't know what to do.

My Macbook White Unibody 6,1 (A1342) started shutting down randomly. It happened for a while and then suddenly it did not turn on again. When I press the power button, the sleep light goes on for a brief moment and then turn off.

I can only turn on my mac now if I hold the power button for like 5-7 seconds. If I release it earlier, the light goes off. I can even hear the HD turning off when I do this.

Also, now when I close de lid and open it again, the mac turns off instead of waking up from sleep state.

I've already done a SMC and PVRAM reset, but nothing worked.

Any clues?? :confused:

102020
Sep 4, 2012, 09:57 AM
Truly, this is not a Mac problem, we have an IBM x3500 server which just started with the same symptoms last week. It's absolutely a hardware issue, I'm putting in a replacement server for us today to get the system stable again but will be diagnosing to find out if it's an issue with 1 of the 3 possible causes:
1) bad ground (doubtful)
2) faulty switch unit (switch itself and/or wiring)
3) faulty mobo (probably the case)

will post back with my finding. In my case, I took some duct tape and taped the button down so it stays on...+1 for macgyver!

etiennegignac
Oct 16, 2012, 12:22 PM
Has this been figured out? I have the same problem on my macbook unibody late 2008.

New dc-in board didn't fix it.

Brian Y
Oct 21, 2012, 04:00 PM
On a unibody MB you can test this by disconnecting the top case, and see if it still powers off automatically. To do this, disconnect the top case ribbon cable from the logic board, and then power it on by shorting out the pins on the connector (running a screwdriver along the pins on the top of the top case connector on the logic board usually does the trick).

If it powers off, its the board. If it stays on, it's the top case.

etiennegignac
Oct 26, 2012, 03:25 PM
Turns out I replaced the disc drive and it's fine now. I saw other posts too where people were blaming a faulty hard drive.

So I guess we can assume that the macbook will poweroff should there be a hardware malfunction.

noelable
Jan 4, 2013, 03:11 AM
Possible solution

This was the most frustrating issue I ever had with my 2.4 Intel Macbook 10.5.8.

I had exactly the same issue the Macbook would only power on if I held down the power button until reaching the blue screen, if I released anytime prior to the blue screen zip.

Additionally, once on my Macbook would work perfectly until it went to sleep then it would also power off. After two frustrating days, I found an unbelievable solution and I remain completely gobsmacked. I turned the computer off, I CLOSED THE LID, I unplugged the power, plugged in the power and powered on as normal and everything worked, closing the lid was the trick, i couldn't tell you if it's necessary step to unplug.

GOOD LUCK

Sheridansystems
Nov 22, 2013, 11:45 AM
I bought this MacBook Pro from eBay claiming a liquid spill. When opening the case one liquid patch was red located on the top case. The motherboard liquid pads located under the ram were not affected.
Symptoms include normal power on for a half of second, during chime the system shuts down. Hold power button for more than five seconds and system powers up normally, occasionally shutting down when waking up from sleep. DC board checks okay. All symptoms remain when disk drives LCD cables are disconnected all excluding top case. I am going to start with the easier listed fixes working to the hardest until I fix this one, and report back my results.
Thanks for the ideas.