跳转到主内容

Model A1224 / Early 2009 / 2.66 GHz Core 2 Duo processor

123 个问题 查看全部

Mac not powering up.

I've been doing phone repairs for a few years, and a friend has an iMac A1224 which won't turn on. So said I'll have a look, I've never done one, so thought it'll be a good one to learn.

So basically, power it up, screen stays black, but it makes the startup noise (or beginning of it) and just loops on this noise?

Any of you pros know what causes this?

Thanks.

回答此问题 我也有这个问题

这是一个好问题吗?

得分 0
添加一条评论

2个回答

最有帮助的答案

You'll need to pop the display off and look at the built-in diagnostic LED's. This system is a bit different than the newer ones the LED's are located just to the right of the PRAM battery which is in the bottom right corner of the logic board. Here's the IFIXIT guide to get you there: iMac Intel 20" EMC 2266 PRAM Battery Replacement and here's what they mean:

Diagnostic LEDs

The iMac has built-in diagnostic LEDs on the main logic board that can help you to troubleshoot the computer. The LEDs are located to the right of the battery (see photo below).

  • LED #1 Indicates the trickle voltage from the power supply has been detected by the logic board. This LED will remain ON whenever the iMac is connected to a working AC power source. The LED will remain on even when the computer has been shut down or put to sleep. The LED will turn o only if the AC power source is disconnected or the power supply is faulty.
  • LED #2 Indicates the main logic board has detected proper power from the power supply when the computer is turned on. This LED will be ON when the computer is turned on and the power supply is working correctly.
  • LED #3 Note: This LED is not used on systems that have integrated graphics, which includes some configurations of the iMac (20-inch, Early/Mid 2009).
  • LED #4 Indicates the computer and the LCD display panel are communicating. This LED will be ON when the computer is turned on and video signal is being generated. If the LED is ON and there is no image on the LCD display panel, the LCD display panel or inverter might be installed incorrectly or need replacement.

这个答案有帮助吗?

得分 2

评论:

Awesome. I'll have a look tonight.

Very helpful!!!! Thanks very much.

完成的

Once you know whats up let us know. Good Luck!

完成的

First 2 are on.

Last 2 are off.

Fan is running,

完成的

Is there a LED #3 here? It just may not be present.

If this is the integrated graphics model then the whole logic board needs to be replaced. If its the MXM card version then the GPU card needs to be replaced.

完成的

There's 4 LEDs

First two on.

Last two off.

When I power off/on. The 3rd led will quickly flash once (or go to power up but doesn't)

完成的

显示更多的2条评论

添加一条评论

It could be that internal graphics card has gone bad. Either that, or a cable has become disconnected internally. There are pages on iFixit that can show you how to disassemble the computer and run diagnostic tests to determine if it is the graphics card.

这个答案有帮助吗?

得分 0
添加一条评论

添加你的答案

Duane 将永远感激不已
浏览统计数据:

过去的24小时: 0

过去的7天: 0

过去的30天: 0

总计 169