Dongfeng commercial vehicle in-vehicle music is connected to the truck audio to play as follows.

The first type: Bluetooth. . Turn on Bluetooth in the car and Bluetooth on your phone and connect. Just turn on the music on your phone.

Second type: You need an AUX cable, which costs about thirty or forty yuan, and then find the AUX interface in your car. For your iPhone 4s, you also need an Apple plug adapter. The converter for the AUX head probably costs tens of dollars. Once you have all the accessories, assemble it and select AUX in the car.