Archgrove

I spent a lot more time at home over the holidays than I do normally, and so my trusty iBook has become less of a laptop and more of a desk ornament. After a few days of sitting there, plugged in permanently, it started giving me shocks via the metal components on the case. Nothing serious, just a small tingling, so I wired up my multi-meter and sure enough, there was a small current flowing whenever the machine was connected to the mains.

I guess I’d never noticed before because it spent most of the unplugged, and being curious more than worried I decided to give Apple a ring. Apple support is still some of the best in the industry and after a minimal amount of time on the phone, they said they’d contact me with a resolution. Well, true to form, they called back two days later with the following interesting snippet.

The power adaptor that Apple ships supported two methods of wall connection. There’s an AC power lead (e.g. a long cable with the plug in the end) as well as a wall plug that slips right onto the adaptor. Because my desk is well supplied with sockets, I’d just slipped the wall plug (the Apple support person called it a “docket” [sic]) onto the adaptor and into the wall. It transpires, however, that this plug is ungrounded.

Sceptical and surprised, I said I’d try it and sure enough, my laptop no longer shocks me when plugged in via the longer AC lead. Not being an electrician, I can’t say why they didn’t connect the ground for the small plug, but it certain seems to be the case. I’d also been experiencing trackpad problems (it was getting stuck in scroll mode), and these problems also went away when the unit was grounded. I understand the trackpads work on a capacitance difference between fingers and surface, so perhaps this also cured that problem (though this just speculation).

Anyway, issue resolved. Hopefully this information can filter through Google and save someone else a call to technical support.