I have a 2004 MCS and the aux input use to work just fine with my iphone. Then all of a sudden one day it started switching back to the radio while i was listening to music on my iphone. This is without the phone being charged. The aux mode worked occasionally, but now it doesn't work at all. I can't get it to switch to the aux mode and i currently have no cable plugged into the aux port in the glove box. I've read that a ground loop isolator has been the solution for many, but since it doesn't work with nothing plugged in, would it apply in my case? Any other suggestions on what could be the cause?

 

without a charger also plugged in you should not be getting the ground loop issue IMO

I'd try two things ... first, try some other device like a simple MP-3 player. I keep an old cheapo MP-3 around just for this sort of a test. If it works, sounds like an iPhone issue

In no joy ... maybe the AUX cable has just wiggled loose from the back of the head unit.

this file is the adapter install instructions and you can see how it plugs in ... with a little wiggling behind the radio you can usually get your fingers in there and try futzing with the cable ... push it in ... unplug it and plug back in ....

http://www.minimania.com/pdfile/NMI7647_INSTR.pdf

 

Thanks for the reply. I will give it shot this weekend when I have time to take the radio out. Any other suggestions?

 

many people have installed the AUX without pulling the radio

you CAN get your fingers back there . . .

 

Ok I will give it a shot when I get home tonight. I will provide an update. Hopefully this fixes the issue. I'm tired of listening to AM talk radio all the time.

 

Taking the radio out is not hugely difficult and much less fiddly.

Sounds to me like you may be chasing a failed component in the aux kit, which can happen over time and vibration.