Repareer je spullen Gemeenschap Winkel

Model A1419 / EMC 3070 / Mid 2017 / 3.4, 3.5 or 3.8 GHz Core i5 or 4.2 GHz Core i7 Kaby Lake Processor (ID iMac18,3) / Retina 5K display. Refer to the older iMac Intel 27" Retina 5K Display (Late 2014 & 2015) guides as the system is very similar.

293 Vragen Bekijk alle

Opties

iMac shuts down, and restarts randomly

I’ve been having an odd issue with my iMac. It starting having this behavior where it will randomly shut down. Sometimes it’s an hour into using it, other times it’s when it’s booting up. Sometimes, when it chooses to shut down, it chimes and tries to restart several times. Chime - Chime - Chime. Sometimes it fully boots, other times it turns off and requires an SMC reset.

Everything pointed to a bad PSU, so I ordered one from iFixIt. I pulled a LiteOn PSU, and installed the Delta brand PSU from iFixIt. The Delta replacement part was used.

Pretty easy swap, however my issue persists. I thought maybe the PSU I got from iFixIt was bad. Contacted them, and they sent me a replacement. This time it was a LiteOn PSU. I swapped it out, and still have the issue.

Last night, it played a looping movie all night long (never shut off). As soon as I got up this morning, starting opening apps and such, it shut off.

My son plays Fortnite on this iMac. Sometimes he can play it for hours before it shuts down. Sometimes it lasts 10 minutes. Sometimes it won’t even get past the Apple logo on startup.

Things I have tried:

  • Using the computer in a different room (different circuit/breaker).
  • Swapped the PSU twice
  • Tried a new power cord
  • Installed new RAM
  • Did a clean install of Catalina
  • Checked temps during heavy usage (all good)
  • Viewed LED lights on logic board (all good)

So what’s the deal? I probably have a bad logic board, right?

Random bits of details:

  • I discovered that the surge protector the iMac was plugged into was not grounded. This was before I replaced the PSU. I purchased a new surge protector, then replaced the PSU when that did not alleviate the issue. I have heard that these iMacs are picky about being grounded.
  • I have a lot of devices on the same circuit/breaker. I have unplugged everything else (except the iMac) and the issue still persists.
  • I have a new iMac in my office that works fine, so I don’t think I’m having a surge issue issue, or some other issue with the quality of electricity coming in.
  • I’ve done lots of testing, and I guess I can chock most of it up to “chance.” For example, my son was playing XBOX (same room). When he turned it off, the iMac restarted (it was asleep at the time). When I tried to replicate, it did not happen.

Idling:

Block Image

During Video Encoding:

Block Image

Idling after Encoding:

Block Image

Beantwoord deze vraag Dit probleem heb ik ook

Is dit een goede vraag?

Ja Nee
Score 0
Voeg een opmerking toe

2 Antwoorden

Filteren op:
Meest nuttige Nieuwste Oudste

Opties

I think you need to dig deeper into your power services. Check your outlets with a cheap outlet checker like this one

Block Image

Here’s a good vid on why A MUST HAVE TOOL - The Electrical Outlet Tester

You also need to check your breaker panel ground connection it needs to hook up to a metal pipe exiting your home or tied to one or more grounding rods. Make sure the connections are not corroded up and if the rods are covered in green oxide they will need to be replaced.

You should also ask your power provider for a power meter which monitors your power feed from them. All it does is plug into an outlet for a few days or better a good week. This should be a free service.

Instead of using a surge suppressor get a good UPS like a APC SmartUPS unit as it fills in voids and holds sync of AC frequency if your power supplier looses it during power feed change-outs from the different suppliers.

Was dit antwoord nuttig?

Ja Nee
Score 0

8 opmerkingen:

I completely failed to include all of the checks I made to the power in my home. I have not checked ALL of the outlets in the house with an electrical outlet tester, but I did test that circuit for ground (all good once I removed the bad surge protector). I had already inspected the ground in the home (attached to water line - looks good). I have a relative that is an electrician. I picked his brain a bit, and did everything he suggested. The power meter from the local electrical company is a good suggestion, and I will have to look into that.

Additionally, I have taken the iMac to a different location and it has the same issues on a completely different electric company. So, either I have cooked something inside the iMac with my electricity, or the electricity is not the problem and my iMac is just dying a slow death.

Bit more detail I saw this morning: I was playing a movie in Plex, and the screen went completely solid green. Stayed that way for 10-15 seconds, then restarted itself. Booted to the desktop without issue. Started a movie again. Played for a long time. Screen went completely solid red for 5-10 seconds, then it shut down. Took an SMC reset it get it to power back on.

Graphics card/logic board issue maybe?

I know we are coming up on 7 years old on this Mac. I always buy a new mac every 3 or 4 years (depending on Apple current cycle refresh). I've had my current "work" iMac for 2 years, and I wasn't in the market to get a new one, and give mine to the "house" as the family computer. Was going to wait another 1 or 2 years (hopefully after the Apple Silicon transition). Now I am in a pickle because the family computer is now a 2012 Mac mini (that barely chugs along).

door

I'm still using a 2011 27" iMac without difficulties! Don't upgrade unless you need the added performance, RAM or storage speed.

OK, lets check thermals install this great app TG Pro lets run it awhile and then take a snapshot of the apps main window (make sure you get all of the sensors captured and post it here for us to see Voeg afbeeldingen toe aan een bestaande vraag

door

Okay. I've added those images. I provided a screenshot of the computer at idle, during an encoding of a video, and idle after the encoding.

door

Did you get the power company to plug in a power meter in your house? Why don't you have them plug in the same outlet your computer is connected to.

You maybe exceeding the circuit from your breaker panel and the outlet you are using. Is your outlet dedicated or is it been shared with other heavy devices (like your sons Xbox). Is the breaker the outlet is on a 15 Amp or 20Amp?

While your breaker may not trip you can be pushing the limits of the outlets wiring. Aluminum wire can loose voltage as the load increases (the wire even heats up and expands unlike Copper wiring). The gage of the wire may not be large enough either do to the distance between as well as the able to support the heaver load.

door

I asked the power company about the power meter you mentioned. They said they offer no such device.

The iMac is pulling power from a 20 Amp breaker. Yes, it is shared by other devices on the same breaker (XBOX, TV, Receiver, etc.). However, the iMac's issue still persists when powered elsewhere in the house. I even took it to my father's house, and it did the same thing.

Home is wired with copper (home is 15 years old). An electrician has looked over my situation, and doesn't see anything that would be causing this issue (in regards to wiring, electricity, or over-amperage).

door

3 commentaren meer tonen

Voeg een opmerking toe

Opties

Hi Andrew,

I’m having the same problem with my 27” iMac I bought in 2016. I can’t update the OS because of the shut downs. I haven’t performed the extensive troubleshooting you have done, but it’s not my electrical system because it did the same thing at another house as well.

I’ll be sorely disappointed if my expensive machine simply stops working after 6 years, and I won’t make that mistake again.

  • Big Sur 11.0.1 (20B29)
  • iMac (Retina 5K, 27-inch, Late 2015)
  • 3.2 GHz Quad-Core Intel Core i5
  • 8 GB 1867 MHz DDR3
  • AMD Radeon R9 M390 2 GB

I live in a metropolitan area and don’t think it’s an environmental cause for the shut downs.

Any solution to your problem?

Meg

Was dit antwoord nuttig?

Ja Nee
Score 0

2 opmerkingen:

I've given up on the machine.

I had it working flawlessly as a Plex client (its only purpose). I had the display temporarily taped in place, in case I needed to open it again.

After a month or so of good behavior, I decided to fully seal the display with proper adhesive strips. I removed the display, and placed the adhesive. When I went to place the display, I temporarily connected the two display cables, and the iMac would power on, but not display a picture.

I figured I had damaged either of the two cables, and decided to replace the DisplayPort eDP cable. It didn't fix the issue. Since it would power on, I decide to make it a headless Plex server. This worked for about 3 or 4 days, when it completely died and would not come on.

At that point, I was completely done. I removed the hard drive, and threw the entire thing in the trash. That's certainly not like me (to display such hate to Apple products), but I just couldn't take it anymore. I needed to rid this horrible device from my home.

door

I'm sorry to dredge up the memory, and sorry to hear about your shattered dream that an expensive device should last (more than) four years. I have the same dream.

I'm on 5 years, and I need a working computer. I barely know what you're talking about as far as troubleshooting goes, but I'll study what you've done and see what I can safely do myself. I'm also going to investigate an Apple repair, I guess, because I have limited knowledge. Thank you for the detailed posts, very helpful! I hope you have recovered, and have a successful stable of devices now.

Cheers, Meg

door

Voeg een opmerking toe

Voeg je antwoord toe

Andrew Lamont zal eeuwig dankbaar zijn.
Weergavestatistieken:

Afgelopen 24 uren: 1

Afgelopen 7 dagen: 5

Afgelopen 30 dagen: 22

Altijd: 1,174