I have a pyle pld5mu and the screen is dark

any frequency dials?

No You can't.

http://www.youtube.com/watch?v=xaCnsAoDHUI this is pretty good.

Im afraid that indicates the bulb is dieing or dead.

how much for you stereo for parts

Your GPS system has to have updated maps. Go to
http://www.pyleaudio.com/Home.aspx

and contact them about map updates to your system. If you bought your system from a supplier, THEY should have made sure your system had updated maps for the area in which you purchased it.

may be some connection are broken.. or lost contact with the board..

May not be a problem with the installation, sometimes ya just get a bad one. If you have hooked it up to power, and ground, and attempted to use a speaker outside of the cars wiring, then odds are you just got a bad radio out of the box.. This sort of thing just happens man, but hey that's what warranties are for right?

1-888-318-PYLE Ask for tech support they will sell you one.

Got to the following lik for your manual: http://www.dualav.com/i/product/manual/xd7500.pdf Refrence page 6 for instructions. With the unit off, press open to allow the front panel to slide down. Genetly squeeze the release tab located on the bottom center underside and pull faceplate down and away from unit to remove. To install insert left side faceplate first then push right side to secure. Hope this Helps L8R