Section 27 (Audio And Video (Service Information)): Radio: Operation: Operation
WARNING: This page is about a different car, the 2011 RAM Pickup and 2011 RAM Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
The radio receiver operates on ignition switched battery current that is available only when the ignition switch is in the On or Accessory positions. The electronic digital clock function of the radio operates on fused battery current supplied through the IOD fuse, regardless of the ignition switch position.
NOTE:
USB devices (e.g., camera memory USB adaptors, etc.) must comply with the MSD (Mass Storage Device) standard. This USB terminal can provide power to the inserted device. The devices current limitation must be less or equal to 500mA.