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I have a MacBook Pro 4.1. In the past - from time to time - you could feel a bit of electricity close to the aluminium case when working in AC mode, but now things are getting worse. I can feel the electricity all the time, especially close to the opening button and to the corners. Talking with other MBP users, I have been told that the whole MBP 1.4 series has got this problem and that it is due to the presence of the aluminium case. Is it a known issue? Is there any workaround to properly ground the laptop?

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Tap the case on a dry faucet? :D – Nathan Greenstein Jul 17 '11 at 14:15
Possible duplicate of MacBook Air passing me electricity. Answers there cover this question. – mspasov Jul 18 '11 at 13:18
up vote 7 down vote accepted

The mac can only ground itself through the magsafe connector if you are using a grounded plug. In the us - the "duck head" two prong connector is ungrounded.

The adapter article from Apple has some good tips and a nice picture.

enter image description here

You shouldn't be able to feel any tingle due to you being better grounded than the mac if your outlet is properly grounded.

You'll have to check with an electrician or take your mac to another outlet that is known to be properly grounded if you are already grounding it through the wall if you still feel the tingle with a grounded cord.

This sort of ground current drives me nuts (even though it's normally totally safe). I have on occasion intentionally grounded one of the plastic feet with foil when I am waiting for the electrician to fix an outlet or I am working in a location where I can't get a proper ground.

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Well I have just experienced this tingle on my Macbook Pro with the magsafe 85w power supply and the 3 pin plug lead with a UK 3 pin plug.

I could not believe that Apple would not earth the machine via the magsafe adapter, so I detached the power lead from the 85w power supply block and took a look how they earth it. The power supply block has a 2 pin connection for live and neutral and the earth connects via the 10mm dia stainless steel stud that the plug lead [or the plug with no lead] slips over to lock it onto the block. Then I saw the problem! On the end of the 10mm stud, the manufacturer had put a 12mm disk of protective plastic [the peal-off film type that you often find on say a new phone screen]. So in their efforts to keep the stud looking shiny and polished, they insulated it from electrical connection, that is they insulated the EARTH STUD !! Just peal it off, plug it back together and [unsurprisingly] there is no more tingle from the alloy case.

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Great catch - I've unwrapped so many plugs, it's not even something I consciously think about when removing the plastic from the power adapters. This would certainly be a great thing to check! – bmike May 31 '12 at 13:02
I've been having this problem with my MBPro6,1 17" (circa 2010) which gets much worse when I attach a Lacie flat panel display. As per Paul Churchill above, I find that by replacing the 2 blade quick connector on the power block with the supplied cord which has a 3 prong connecter, I become better—though not fully—grounded. BTW, I'm in North America. t – user89512 Sep 3 '14 at 1:04

Use the extension cable that comes with the magsafe as that has an earth connection to the 10mm stud which is not present on the non extended plug block

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There is no protective plastic On the end of the 10mm stud with any of the 2013 models. So what you are saying, Paul Churchill, is incorrect. The problem with electrical current flowing through all the MacBooks can not be fixed. Only Apple can fix it, but they don't want to fix it.

Of course it is unhealthy & unnatural when an external electrical current flows through your body, no matter how small. It messes up your whole electrical system in your body. All nerve signals, all organ and all functions in general in your body function through the bodies own electrical current system.

I have noticed it too, and will return all my Apple products that conduct electrical current. So please watch out if you care about your health and don't want to get seriously sick in the long run.

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"Apple" isn't going to delete this content, because this website is in no way affiliated with them; this is a community-run Q&A site for Apple products. If your answer is downvoted or flagged for deletion, it's because visitors to the site found it unhelpful, or it was determined by the moderators (also community members) to fall under these criteria for deletion. – Dan J Nov 18 '13 at 22:37
I would welcome a reference to explain the criteria for what level of current you feel is unhealthy. Your initial post comes across as folk medicine/FUD without some sort of rationale why electrons on the surface of your skin are "unhealthy & unnatural" since if that were true, any child with a balloon and sweater would be at risk. – bmike Nov 18 '13 at 23:30

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