My truck came with the non JBL entunes with app as far as the unit head . I bought a JBL head that has the Nav system as the stock made you use the Scout app. I then bought a refurbished JBL Toyota amp that came with a plug and play harness. I hooked everything up and I am only getting sound from the front three dash speakers and the rear door tweeter speakers. Under the passenger front seat was the previous box that had two pin connectors that worked with the previous head unit. I am assuming somehow these pins power the 4 door speakers that are not working.