factory head acdelco aftermarket subs

I have a 2001 Cadillac Deville The factory stero is still in and there is a line out converter in the trunk running off the old speaker wires. I have replaced the rear deck speakers with alpinr 6x9's and a pioneer 10 inch sub in the center The problem is the amp turns on but no sound is ever heard from the speakers. Sometimes I can turn the line out converter's switch back and forth and the amp and speakers will come on. I have from reading several forums picked up that there is a factory amp in the system as well. I think that the factory amp is not turning on and therefore the speakers in the rear are not getting any output becuase of that. The factory sub has been removed from the car fo course, I have read that will cause the factory amp not to turn on. But if thats the case would ALL speakers stop working? Or just the rear deck? If thats not the case why only the rear deck speakers are not coming on? If the ampo LED is showing the ampo is on. Why am I still not getting signal heres a diagram of how its setup

http://www.fox302.com/userdata/treshawn/files/webpics/gifwiringdiagram2.GIF

that factory amp might be too much power for you line output converter

So after some fiddling I figured out that if while playing I cross the speaker wires heading into the cannon plug the system starts working. If i disconnect and wire it this way, the system will not come on. Only when the amp is on, and radio is playing, if i cross the speaker wires it will play IE you havce a left negative and left positive and right neg and right pos if i touch a wire between three of them IE a wire that touches LN. LF and RN, it will start playing, i can then remove the wire crossing and it will continue to play while the car is on As soon as i turn off, i have to do it all over again, WHAT GIVES?