跳转到主内容

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!

回答此问题 我也有这个问题

这是一个好问题吗?

得分 1
添加一条评论

3个回答

最有帮助的答案

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.

这个答案有帮助吗?

得分 1

评论:

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.

完成的

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.

完成的

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

完成的

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

完成的

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

完成的

显示更多的1条评论

添加一条评论

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...

这个答案有帮助吗?

得分 1

评论:

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

完成的

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?

完成的

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?

完成的

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

完成的

添加一条评论

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.

这个答案有帮助吗?

得分 0
添加一条评论

添加你的答案

James mcshea 将永远感激不已
浏览统计数据:

过去的24小时: 1

过去的7天: 16

过去的30天: 48

总计 1,317