[JUAN2011E92]

Hey guys, well my AUX in my car does not work i donno why.. volume is good on the radio aux input, on the phone, there is no sound when input is chosen ,not even static if i move it around. I checked all the connections (under the arm rest, i removed the aux thing from the ac duct and checked every connection. It was all good). Im thinking maybe i need to have the aux coded by the dealer..is that a possible reason?.. Or im thinking the Aux plug is bad.
Well so im looking at a retrofit for USB. If any of you have a GROM MST4 or anything that can work, Or if yoguys can code the aux or have a clue about the aux. please let me know its annoying. My car does not have a MULF on the back, i read about that and i checked. My friend has the same car, no MULF and working aux.. Any ideas guys, thank you