Purchased in 2001, upgraded memory, hard drive and OS. Hinge/wires broken

PowerBook g4 titanium purchased in 2001, upgraded memory, hard drive and OS. Left hinge and display wiring shot but it still chimes. Located in tact lower case and display. Seller removed his hard drive and suggested a backup clock battery was the reason it shows no signs of life. I put my hard drive in it. What should I do next?