Pioneer GM-1000 wiring connections

Hi, I'm struggling with a Pioneer GM-1000 amplifier. I bought a din 8 connector and I have difficulty understanding the connections to be made to the pins in order to test it with an incoming audio signal. Following the diagrams I found on the net, it is indicated to connect a +12 which gives the power on signal of the amplifier and a service that I do not know where to get the signal from. Also the amplifier has a 12v battery backup and negative input and another 12v and negative connector near the speker output. Now which of these voltage connections need to be made to make it work? Thank you