Rear Speaker Problem

[Dooka]

I just bought a 96 4runner. The rear speakers do not work though.
It was a Kenwood Aftermarket HU in it. I have done research, and "heard" about the rear speakers being on a different amp that must be bypassed OR the rear speakers are running through the antenna, some say the Factory HU is the only way to get sound, etc....
I have tried radio and regular CD setting and I still have no sound to the rear speakers.
Does anyone one how to get the rear speakers working?

Thanks!

 

[Dooka]

Some more info about problem

The rear speakers do not work.
I took apart the head unit.
Coming from the car I have:
2 orange (stripe and no stripe) that are tied off.
2 purple (stripe and no stripe) that are tied off.
and a blue antennae wire that is tied off.
FYI. there is a blue another blue wire that is going out of the white chassy thing and right back into the white chassy thing only a different port.

Coming from the head unit, I have:
2 orange wires (stripe and no stripe) that are tied off
2 green wires (stripe and no stripe) that are tied off.

 

[jaypapa]

I just upgraded the HU on my 2000 and had my notes handy:

Orange = illumination
Orange&White = dimmer (I didn't use)
Purple = right rear speaker +
Purple&Black = right rear speaker -
Blue = power ant

Also for reference, green = rear left speaker

I suspect the purple not being connected is the problem.