2005 Corolla LE stereo installation

[scarah]

I currently have the JBL system with a 6 CD changer. I want to replace the radio. In the back is a 20 pin connection only. I purchased a 20 pin premium wiring harness that was recommended to me by a company (it uses RCA connections for the speakers). However, it is not working (radio has power and seems to be working ok, but there isn't any sound).

I now suspect that I don't have an external amp (can somebody please confirm or deny this?). I also would like a wiring diagram for the car's harness (I have yet to find a diagram in the internet that matches my connections). I don't have any problem wiring by hand, but I want to know for sure what I am dealing with.

Thanks!!

Additional Info (car harness wiring along with assumed function)

1-grey (ignition power)
2-white/black (dimmer)
3-black (power antenna)
4-empty
5-purple
6-empty
7-empty
8-white
9-green
10-brown (ground)
11-blue/white (battery power)
12-green (illumination)
13-empty
14-empty
15-pink
16-empty
17-white
18-red
19-black
20-covered in black electrical tape

I can't figure this out because there are less wires than would be necessary for the speakers, arguing for an external amp. Any help would be appreciated.

[MrGiggles]

Since you have an upgraded sound system from the factory there is probably an amplifier in there somewhere, where I can't tell you.

To utilize the factory amplifier you are going to have to buy a special harness that has the remote on for the amp and RCA or speaker connections for the signal.

Most repair manuals have a wiring diagram in them, maybe you could check that. The best option is to get the needed harness though.

[ryan_t888]

This was for my 04 Corolla CE. I did the installation myself without any harness. This is for a stock standard system. I do not have the premium system.

(+)12v Constant - Blue/White
(-) Ground - Brown
(+) ACC - Gray
(ILL) Illumination - Green
Power Antenna - Black
Car Stereo Dimmer Wire - White/Black
(+) Left Front Speaker - Pink
(-) Left Front Speaker - Purple
(+) Right Front Speaker - Green
(-) Right Front Speaker - Blue
(+) Left Rear Speaker - Black
(-) Left Rear Speaker - Yellow
(+) Right Rear Speaker - Red
(-) Right Rear Speaker - White


Is there still 2 Looms of wire for the premium system? The 2 looms on my CE were seperated like this:

Loom 1
Red + RRS
White - RRS
Black + LRS
Yellow - LRS
White/Black - Dimmer Wire Not used

Loom 2
Blue/White + Constant
Brown - Ground
Grey + ACC
Green ILL
Black Power Antenna Hook
Pink + LFS
Purple -LFS
Green +RFS
Blue -RFS

For your external amp, you may use the new remote lead off of your deck, or you may run it off of the grey accessory wire. Either way will run the remote turn on wire.

Ryan