How do you wire in car radio if there is no plug in the back,just a pin connector?

Question

Alpine and Jensen units,no wire plug in it,no diagram on top.

One Kenwood has nine colored wires out the back,Who's who ?How do i find out.

Answer 1

Red wire is battery, blue is remote,black is ground, yellow is ACC, all the rest  should be two of the same collor with a line down one of the two they may match to the cars or may be slightly off, insted of green they may be light green, instead of purple maybe a light pink. any more you can tell me about the radio?

Answer 2

can you b more specific?