Touchscreen (digitizer) inaccuracy when plugged in.

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Level 1

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Touchscreen (digitizer) inaccuracy when plugged in.

All,
I've been noticing that after my iPhone 4 is plugged in for a while, the touchscreen no longer registers touch instances accurately. This is particularly frustrating because I plug my iPhone in while I'm using it for gps navigation in my car and it's virtually impossible to manipulate anything in the application due to the touchscreen inaccuracy. Has anyone else had this issue? Is Apple aware?

iPhone 4, iOS 4

Posted on Aug 5, 2010 7:12 AM

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Answer 1

Dave Hutch

Level 4

1,491 points

Aug 5, 2010 7:42 AM in response to bvsciguy

Absolutely. I found that if you touch the band around the phone with a finger, the screen reacts normally.
Haven't quite pinned down the problem yet but must be an earthing issue.

I've tried a non-Apple cable and two Apple cables and they all behave in the same way:

All three cables (and the screen) don't work if you don't touch the outer band when plugged into my cheap mains plug.
All three cables (and the screen) work correctly when used with a computer's USB port.

Tomorrow I'll try the Apple mains plug that came with the iP4.

(Having said that though, my car connector works fine and I can operate it one handed - Griffin PowerJolt SE)

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Answer 2

Dave Hutch

Level 4

1,491 points

Aug 6, 2010 12:59 AM in response to Dave Hutch

OK, managed to test the Apple USB Mains Plug against the non-Apple USB mains plug and the fault is in the plug.
The Apple one works fine so I can only assume it's a mains earthing issue.

Worth thinking about, even though the savings are £14 for a cheaper version of the plug. This may also apply to other models.

Apple Plug
!http://davehutchinson.zenfolio.com/img/s10/v16/p50561757.jpg!

Non-Apple plug
!http://davehutchinson.zenfolio.com/img/s9/v14/p321473229.jpg!

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Answer 3

bvsciguy Author

Level 1

0 points

Aug 6, 2010 6:37 AM in response to bvsciguy

That's interesting because my problems show up when using the Apple plug. Do you think it could be a grounding issue with the car or the inverter I'm using?

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Answer 4

Dave Hutch

Level 4

1,491 points

Aug 6, 2010 7:28 AM in response to bvsciguy

That's my theory. Do the problems go away if you touch the metal casing of the phone with another finger?

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Answer 5

Probz

Level 1

0 points

Jan 23, 2011 4:50 AM in response to Dave Hutch

Thats exactly the case. When i touch the back side of my metal casing the problem seems to vanish.
please help out. Its irritating 😟

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