Ok I got a EF fairmont ghia with the premium sound system,

I got a new double din touch screen deck for it as the old one was playen up a lil
I installed it all lastnight got the front speakers all hooked up and working but with the rear they run off the amp along with the sub, I wanna keep the existing amp and speakers with sub….

At the deck it runs 1 big plug with 4 wires 3 are big black ones (rca) and 1 blue one to power the amp, ive hooked the amp one to the accessories wire,
But not 100% sure what to do with the rca wires? As there are 3 rca’s yellow, red and white. And only 2 at the deck like normal. (white and red)

What do yas recommend?

Was thinking of running new rca’s but like I said there are 3 at the amp and 2 at the deck?

Thanks,.

I would assume that the red and white are your left and right and the third on would be for the sub. You need a xover that will provide the low pass for the sub and high pass for the rears....