Does anybody know where the J4 jack is located in the truck for the head unit aux enable signal..???? I have J1 and J3 on the head unit which is a CD am/fm stock unit without sirius radio or 6 cd changer. It is a single cd player on my head unit. I am trying to figure out how to enable the aux input on J3 plug. but the input is supposedly on J4 which I am not able to locate. My head unit is a 5L3T 18C869 AC unit... by the way the only plug used on my unit is J1 (speaker, power, etc) by the way supposedly J4 is a 8 pin connector and has Aux Aud 1 and Aux Aud enable signal on it...

 

AS I understand it,the AUX option is only on the Audiophile HU(6cd changer).The aux is for the overhead entertainment system. That said,check out WWW.Logjamelectronics.com for a adapter.
Good Luck

 

Yes, the Aux is for the RCA jack inputs on the OEM DVD system.