Trust this computer


Staff member
Aug 16, 2005
New England
What's at the other end of the cable? (is the USB port built in to your car, head unit, or is it a 12V charger).

the phone recognizes the charger as a computer due to signals on the data lines. The middle two pins/wires in the rectangular USB connector. You may want to look for debris in there as an intermittent contact may cause this kind of behavior.



macrumors 68030
May 16, 2011
Eau Claire, WI
I would say it is how your payer in your car is handling it, anotherwords it sees your HU in your car more as a computer more then anything.

my Pioneer in my car work just the same with my IP6 (IOS 8) but it is just a basic cd player with usb port. You may have a more complex system then me.


Staff member
Jan 23, 2005
Every time I charge my phone in the car it now asks "trust this computer".

It asks me every time I charge!
Same here with iPhone 6. I think this is a bug in either iOS8 or iTunes.

I am connecting using the new cable that came with my phone directly to the USB port on my MacBook. Swapping cables does not help.

I don't get it every time though. I get it when I notice wifi sync stops working when iTunes can't find the phone over wifi. Then I restart the phone to get the wifi sync working again (this works sometimes) and when it does not I attach with the cable and get that message. The message would explain why the wifi sync stopped working, but no idea why iTunes is losing track of the fact I have authorized this phone to sync.

The odd thing I notice is when this happens, the Phone "name" goes back from my personal name to the default "iPhone" and I have to rename and sync to get the name back.
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