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iOS: Troubleshooting car stereo connections
Beginning playback and controlling music
If it is and you cannot hear sound from your car speakers, try switching to your radio and then back to the proper input.
Disconnect and restart
Isolate the issue
Try to reproduce the issue with an identical or similar accessory, if one is available, or test with a second device.
Restore iPhone, iPad, or iPod touch
Best of luck,
thanks, as best as i can tell, i've isolated the problems to the ios7 update.
i have two cables to connect my iphone5 to the car usb - one apple, one not, and both have the same problems showing up as unsupported cables. neither one connects to sync on the car reliably (or fails consistently either).
often sync claims that no usb device is connected, even though sync was just playing through usb moments earlier and the charging indicator shows the phone is connected. disconnecting and reconnecting used to fix this, even if it took several attempts, with ios6. now, after a dozen+ attempts it doesn't connect. power cycling the phone, the radio, the car - nothing makes a difference.
i'm having trouble controlling playback via sync now too, that i never did before.
my iphone3gs running ios6 connects with the same success rate as it always did (about 75% of the time it's fine).
i will grant that ford's sync system is pretty lousy, but at least pre-ios7 i could eventually get it to work. no longer.