i just recently bought a Boss BV7320 and ive got all the wires hooked up.. but i can't figure out why it isn't working.. when i go to start it up it just keeps flashing.. ive figured its somthing with the ground wire.. and when i touch the ground wire with bare metal it just flashes and doesn't come back up.. i can't get the screen to even come up.. there are 2 notes on the page where i am reading the instructions and i am confused in what it is telling me to do... the notes are (1. parking wire must be connected. parking brake must be engaged in order for the mointor to work. 2. use the clip end of the ground wire provided by the manufacturer to connect the mounting screw, use the other end of the ground wire to connect the negative pole of the power source. Otherwise, the video on the screen may flasches) these notes are exactly word for word.. ... please help

picture of radio
http://www.amazon.com/BV7320-3-2-Inch-W ... words=boss