Panasonic Rear Projection

I have a Panasonic rear projection tv. Older Model. ( model - PT 51hx40b. ) It comes on but no picture or sound. Someone told me to check the PC board. I pulled it out and saw that it looked alittle dark in one spot. Would this could this be the problem? I tried to just order the board but every site I have been to including Panasonic says that it is discontinued and no substatute part.  Thank you.