メインコンテンツにスキップ

修理を始めるには

修理する権利

ストア

モデル番号A1311 / Mid 2010 / 3.06 & 3.2 GHz Core i3もしくは3.6 GHz Core i5プロセッサ

380回答 すべてを表示

iMac Shuts Down after First Chime & Apple Logo appears

Hi all! I’d appreciate any advice on this super annoying problem I’ve encountered with a project iMac I’ve been working on. Long story short, I picked up this iMac on OfferUp for $15 with the only “issue”, according to the seller, being that the LCD screen was somehow broken. Upon further inspection, the connector to the logic board for the LVDS cable was ripped from the board and was completely missing. Here’s what I’ve done so far:

• Replaced the logic board with an identical one that HAS this missing connector

• Replaced the CPU/re-thermal-pasted it into the new logic board

• Reconnected EVERY bit of cabling and all of the connectors inside the unit

When I power on the machine, each of the “good” diagnostic lights turn on, and the screen works – YAY! However, the machine will turn on, chime, give me the Apple logo with a status bar, and then within 5-7 seconds of chiming, it spontaneously shuts down. I suspected the hard drive, so I created a bootable USB installer of High Sierra and booted the machine into Startup Manager so I could choose the USB; this works, but the computer still shuts down before I’m even able to select the USB.

I’m now considering the power supply, but I’m not fully convinced that this is the problem because the machine is clearly getting power; does anyone have ANY idea what the issue could be here? I’d appreciate any insight at all, thank you so much for reading!

EDIT: Please see the following photos (the first is the original PSU that I pulled from the iMac, and the second is the PSU that I purchased on eBay for my particular A1311 model).

Block Image

Block Image

この質問に回答する 同じ問題があります

この質問は役に立ちましたか?

スコア 0
コメントを追加

1 件の回答

最も参考になった回答

Britt,

Seems like you're doing all the right things. Since I don’t know your background I’m going to take a very high risk of mentioning something you already know. Please don't be offended if you have already tried the following:

I’m assuming you have attempted to log in using Safe Mode.

Have you tried holding down the “C” key when your going to Startup Manager? This will tell the Mac you want to boot from the USB without having to select it in Startup Manager. I doubt this will help as I’m gonna assume it’s still going to shut down.

Have you tried holding down the “D” key so you can attempt to run some diagnostics?

What about ⌘V for Verbose Mode? You can probably skip Single Use Mode.

If after all this your computer keeps shutting down, it could very well be the power supply as you originally suspected, if it’s happening shortly after boot up. If you have a Multimeter you can diagnose the Power Supply and see. If you’ve never worked with power supplies before, they can cause death if just touch it the wrong way. So please be very careful and be hyper-vigilant for your safety.

Could it be something else? Sure. Knowing the exact model of your iMac would be helpful as well as anything else you have observed, even if you don’t think it’s important. Your experience level too please, so if you're a tech ninja, then I won't risk offending you with what would be obvious to you.

Let me know if I’m on the right track or way off.

Best wishes,

Eddie

このアンサーは役に立ちましたか?

スコア 1

コメント:

Hi, Eddie! Thank you so much for your response, I would certainly not consider myself a tech ninja (hah!), however I do have quite a bit of experience with taking machines apart and putting them back together, upgrading/replacing components, etc.

I have, indeed, already tried all of the suggestions that you mentioned; none of them work, unfortunately. The machine does completely shut down before I am able to get anywhere. The iMac that I’m working with is a 2010 21.5” iMac (model A1311, EMC no. 2389).

さんによる

@edd1e Because I have suspected the PSU, I went ahead and ordered a replacement for my specific model (A1311) on eBay for $15, so it won’t be too costly of a repair if that is, indeed, the problem. However, I did notice that the PSU that I pulled out of the iMac looks different from the one that I ordered online – not strikingly different, but the new one appears to have a few additional capacitors that don’t exist on the one that I pulled from the iMac. Could this be part of the problem? I'm going to attach the photos in the original question so you can see what I'm talking about.

さんによる

Is the PSU one of these part #'s 661-5299, 614-0444 ? Did you ever try booting with an external monitor hooked up and did it show any sign of life?

さんによる

Hi @mayer , the part number for the existing PSU is 614-0445; I have not tried booting with an external monitor yet; I just assumed that since the computer was dying so quickly after turning on, that using the external monitor wouldn't make a difference. I can definitely try it though, I do have an external monitor that I can use!

さんによる

コメントを追加

回答を追加する

brittcheshire さん、ありがとうございました!
統計データを表示:

過去 24時間: 0

過去 7 日: 0

過去 30 日: 0

今までの合計 103