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MBP powers down after 4 seconds

My MBP shuts down 4 seconds after I press the power button. I had a very noisy fan for the last couple of weeks, got a new one from iFixIt, but haven't installed yet. I've tried most of the solutions suggested by the Apple Knowledge Base at http://support.apple.com/kb/TS2570: Safe reboot, PRAM reset, start from CD plus resetting the SCM. (I mentioned the noisy fan, because that's one of the symptoms Apple describes in its article on resetting the SCM at http://support.apple.com/kb/ht3964.) Until I tried them, I was getting most of the way to the desktop, then grey screen only, now 4 seconds of black until the power goes. Help??

Risposto! Visualizza la risposta Anch'io ho questo problema

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Thank you for that quick answer, remacberlin! However, I've looked through the Installing MacBook Pro 15" Core 2 Duo Models A1226 and A1260 Logic Board Replacement link which you suggested without finding any mention of a backup battery. In which step will it be? And, as I mentioned in my question, I had already tried the steps for resetting the SCM/SMU using http://support.apple.com/kb/ht3964. OK, OK, I'll try the SMU suggestion again...

da

Following the instructions for resetting the SMC for MacBook pro, which I now realize is below the instructions for "Mac portables with a battery you can remove", I get a continued low purr when the power button is released after 5 seconds. When the power adapter is reconnected and the power button pressed again, the purr continues. I then press the power button for long enough to shut the MBP down properly (4-5 seconds); press the button for a second or two until I hear noises from within: still that quiet purr only and a black screen throughout. Switch it off a couple of times--the second time, properly--start it up again: this time I've had it on for more than 2 minutes but still black screen only...

da

Tried next to start up from a Snow Leopard installation disk and got as far as the grey apple on the grey background with a spinning symbol. Everything went black and the MBP shut down after 1 min 07 sec. Help!

da

Tough problem. A history of the machine may prove useful. Were you over heating ever? Tell us about your RAM. How long was the machine off before you tried the 10.6? How's the light on the MagSafe also the LEDs on the battery?

da

Hi, mayer! The machine is more than four years old. As in my original post, the right hand fan (I think) has been noisy for the past couple of weeks (maybe 3-4 weeks altogether now) which is why I got a replacement fan from iFixIt. Maybe it has been running too hot...

da

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Soluzione Prescelta

I agree with "mayer," just remove the battery and start it up. May I suggest that you go ahead and change out that noisy fan that you were talking about. Ventilation is a MUST for these MacBooks, so resolve that first and then start it up. If the same problem happens again then you might be looking at a logic board replacement but, before we assume that it's that do this procedure here first: Turn on the machine and immediately hold down the Command and S keys together, hold them down until you see the apple symbol with the "spinning" ball. Once you see that, let the keys go and let the machine run it's course. When it finishes (after about 1 minute) type in the following info exactly as you see this: fsck -fy, then press the ENTER button. If the machine is still running then just wait until you see the final results displayed. Now, if the system finds problems with the disk it will automatically fix them and the final message will be something like this: The hard drive appears to be OK.

That is what you want to see, now type the words LOGOUT and press enter. The machine will then restart up on it's own, from there you can take it and see what happens then. Hopefully (if the machine does not shut off during that process) your issues may be resolved. If so, what you will realize is that the hard drive was/is the issue and needs replacing, especially if that test found "Bad Sectors."

Update

Alright I just saw your latest response. Now you're getting some kind of action here, what we are now trying to do is to keep the screen up long enough for it to complete a full cycle of repairs. Try this: when you turn on the computer, hold down the "R" key before it boots up and keep holding it down until you get a screen with the spinning ball, then you can let go. What this is suppose to do is to "Reset" your screen. Let's hope this will help.

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Charles, I followed your starting up in Safe mode instructions three times. The first time, I wasn't looking at my watch when the screen blacked out. The second time, the system continued its repairs for about 6 minutes, on and off, (which seemed much longer than the first time) until the screen blacked out. The third time, I couldn't get past the black screen.

da

I take your point about replacing the fan ASAP. I had been having a similar thought but did not act on it because I wasn't sure that it would be worth the effort. Anyhow, I am now 700 km/420 miles away from the replacement fan, which had to be sent from America to Australia, so I guess I continue this correspondence in the new year after I have replaced the fan. Thank you (and Mayer and remacberlin) very much for your advice and happy new year!

da

Another thought: could I try booting my sick machine up from its bootable external hard drive and hope not to get a black screen? What keys would I use at startup?

da

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If a battery runs all the way down the machine will not start without some charge. Therefor if your battery is kaput (it shows no green LEDs) the unit might try to start and fail. So we know the battery is gone, replace it and all your problems may go away. What happens when you remove the battery and try to start from the magsafe?

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Season's greetings, Mayer, which explains why I have been off air for the past 3 days. The battery now shows 4.5 green LEDs--the fifth one is flashing and the Magsafe shows orange as in charging at this time. As the battery is only 18 months old, I'm not ready to say "kaput" yet.

da

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Sounds like a problem with the SMU (System Management Unit) Try resetting it http://support.apple.com/kb/ht3964. Also you can try disconneting the backup battery Best guide for that found here MacBook Pro 15" Core 2 Duo Models A1226 and A1260 Logic Board Replacement And try it without the main battery.

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Success! Before I saw your Update just now Charles, and several days back but it is party time right now, I followed your Safe mode instructions yet again. This time the MBP had been turned off over night. Fourth time lucky! Although I'm guessing that some of the earlier attempts at repair had helped things along. So now I'm avoiding doing anything with the MBP to make the fan labor and it continues to work fine. Back home in a couple of days and installing the new fan will be on the early agenda. Thank you everyone for you advice but especially Charles whose advice contained the solution!

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I also followed Charles' suggestions and my computer is saying Filesystem cannot be checked ... any thoughts?

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asmith sarà eternamente grato.
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