we bought a old model greenmaster 069 model. they took apart so as would fit into our car. we are now trying to put back together, the powe is there as light is on. but no power to display . there are 2 cables red and blue hanging out of the stand that holds the dispay screen (we have screwed that back into place yet) - but cannot see is where these go, or if they are to be attached to something ? need the screen connected up