Mobile 7-inch tv monitor with dvd pla...

couple different scenarios here...first, the previous owner may have had the dpeakers amplified and removed the amplifier before selling the car, or he may have even removed the speakers themselves. ive seen this done alot with aftermarket equipment. check behind the stereo to be sure that the speaker wires are connected to the cars wiring. also peek in the door panels to make sure the previous owner left you with some speakers. after your sure theyre all connected properly check for sound. if nothing, then you have a problem with the unit.