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MacBook will not power on no chime nothing

MacBook will not power on at all. It doesn't respond at all, but when I plug in my charger the light does come on. Sometimes it is flickering though but it's been solid for about a half hour.

The laptop was sitting for a while and now when I went to power it on it won't!

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Can tell us a bit of the history? Also try holding P, R, Option, and Command keys at the same time. Then while holding them, press the power button and hold the keys until u here the chime 3 times.

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It worked fine about a year ago then I let it sit for a year and now I tried to turn it on. No response. Plugged the charger in and got a orange light, nothing, green light nothing. It had a dim green light also. It's never been dropped or had any water spilled on it. By the way the command option P R did not work. It does not respond to pressin the power button at all.

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Oh and I noticed the MacBook had a swollen battery because the touchpad was actually pushed out. I replaced the battery after noticing it and it still didn't work.

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Try holding shift, control, option, and power button for 7 seconds. the adapter light should turn green.

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It's green every time I plug it in now but still no response when I push the power button.

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open up the back and push the power button. see if the fans are running

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Oh, boy. James, given that you had a "swollen battery," it sounds not good! Swollen power sources are often caused by excessive current drain (overheating), which are often a result of a "short circuit," which often remain until the component causing the "short" has heated to the point of decomposition - which results in a new problem, an "open circuit." At that point, repair becomes expensive and not worthwhile. Unfortunately, it requires some skills to determine this. How're you voltmeter / electronic troubleshooting skills? You mentioned you had changed the battery; did you happen to scan the exposed circuitry to see if you could spot any other swollen or blackened components or fried conductors / circuit tracks? As Lord Vader asked, can you tell if the fans start running? Can you check the voltages on any of the components - to see if any exists? This sounds like something more than a mere software problem...

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Thanks for helping him. I haven't learned about this yet. But I hope I do soon

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I actually have done repairs on Mac motherboards and iPhone boards before and my multimeter skills are good enough also. I have checked for fans moving and there is no response all around. I figured that their was a short somewhere but I needed someone to confirm my suspicion. I have looked on the board for burnt out or swollen capacitors but I haven't seen abything yet. Any suggestions where I should point my attention to?

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James, without detailed schematics, it's difficult to tell exactly _where_ to start looking, but if you know where the power supply is, try checking for voltages there, i.e., batt. in and V+ out. If you _know_ where a V+ line/trace/ IC pin is located, try checking resistance to ground. Did you check voltage at the fans? Can you track the fan supply power backwards to the source?

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Sorry, but that is crap information. A swollen battery is usually caused by failing lithium cells. It happened to my Macbook. New battery - PERFECT.

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Try this.

Disconnect all power sources.

1. Hold the 'option' key down.

2. Plug in the power source.

3. Keep holding down the 'option' key for about 5-seconds and then release.

4. Disconnect all power sources and wait for 10-seconds.

5. Plug in power source and power on computer.

This has worked for me on countless occasions.

Thanks to the guys at Stockley Park that told me this years ago.

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James mcshea será eternamente grato(a).
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