WARNING: This page is about a different car, the 2012 RAM Pickup and 2012 RAM Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
Possible Causes
(X300) AMPLIFIED SUBWOOFER 1 (+) CIRCUIT SHORTED TO VOLTAGE
(X390) AMPLIFIED SUBWOOFER 1 (-) CIRCUIT SHORTED TO VOLTAGE