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aPple nErd

macrumors 68030
Original poster
Feb 12, 2012
2,726
667
Jailbreaks/IOS Hacks
ok so i have a 2011 imac 21.5. every time it is even plugged in, it vibrates if i touch it. and it sometimes shocks me. if i have a usb cable from my iPhone plugged in, and i happen to accidentally have my have on the dock connector, it stings my hand... like it's shocking me. it hurts badly. is this normal, or should i take it in to the apple store?
 

Intell

macrumors P6
Jan 24, 2010
18,947
498
Inside
That sounds as if it isn't grounded properly. Is the socket it's plugged into properly grounded? Have you or are you able to try another socket in another part of the house?
 

aPple nErd

macrumors 68030
Original poster
Feb 12, 2012
2,726
667
Jailbreaks/IOS Hacks
That sounds as if it isn't grounded properly. Is the socket it's plugged into properly grounded? Have you or are you able to try another socket in another part of the house?

that's what i initially thought. i have tried 3 different outlets. my house was rewired in the 1980s, and the outlets were upgraded to 3 prong about 15 years ago. so, i don't think it's that, because my mom's 2011 and also her 2012 iMacs neither did this.
 

steve123

macrumors 6502a
Aug 26, 2007
772
391
ok so i have a 2011 imac 21.5. every time it is even plugged in, it vibrates if i touch it. and it sometimes shocks me. if i have a usb cable from my iPhone plugged in, and i happen to accidentally have my have on the dock connector, it stings my hand... like it's shocking me. it hurts badly. is this normal, or should i take it in to the apple store?

Sounds like a serious issue. Unplug the iMac immediately to eliminate the potential hazard and arrange to take it to the Apple Store and have it looked at.
 

smithrh

macrumors 68030
Feb 28, 2009
2,651
1,623
Concur with the others, this is a ground loop or worse. Not normal.

May be an issue with the mac, or something has happened with your wiring since it was redone. The first step is to take your Mac back to the store. You can also buy inexpensive outlet testers at most hardware stores to see if there's a fault in the outlet.

To be clear - it's not "vibrating," you're actually getting some voltage through your fingertips when that happens. You're feeling the AC current frequency.
 

hfg

macrumors 68040
Dec 1, 2006
3,621
311
Cedar Rapids, IA. USA
Most hardware stores sell cheap "AC Socket Testers" which are easy to use (just plug them in to the outlet) and use lights to show faulty wiring. It might be worth it to try one of those first ...

But it does sound like your iMac isn't grounded properly!
 

Shane1905

macrumors regular
May 21, 2012
204
1
UK
Defiantly unplug it now and take it back to the store as soon as you can. It's not actually vibrating when you touch it, that's a small electrostatic charge passing between your mac and you. If there is an earth fault with this it could electrocute you or someone else in your house if fault becomes worse. Hopefully it is a simple fix for them if it is some badly connected earthing. But it could also be a fault with the wiring in your house. It may be worth getting someone qualified to carry out a simple test on the earthing of your home if your replacement mac has the same issue.

Qualified Electrician
 

etichi

macrumors newbie
Aug 1, 2012
20
0
How about try another outlet before hauling your computer to the store? unless you have used the same outlet for previous computers.

-- nevermind. see you tried that..
 

chrono1081

macrumors G3
Jan 26, 2008
8,216
3,384
Isla Nublar
Definitely sounds like a grounding issue. I used to run into this all the time overseas and at my parent house. At my apartment however I don't have this issue.
 
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