Dodge 2004 Ram Pickup 3500 - Manual (Page 174)

An ERR symbol will appear on the display if the laser is
unable to read the Disc data for the following reasons:
• Excessive vibration
• Disc inserted upside down
• Damaged disc
• Water condensation on optics
Radio Display Messages
Your radio has been designed to display certain messages
when a problem is detected with the CD player.
174 UNDERSTANDING YOUR INSTRUMENT PANEL