[HOW-TO] AUX (Line-in) on CTS without sat radio

[Dronix]

Step 3. Installing relay box to the radio.

Take off your radio. Here's a link that can help: http://www.cadillacfaq.com/faq/answers/radbezel.html

Look at your radio's connectors. We need this brown one. Look closer - there are two pair of wires - 2 light greens (L channel), dark green and dark orange (R channel). Cut them, and install relay box. AMP wires to the side that goes inside car, HEAD wires to your radio side.


After that, you can use velcro tape to stick relay box to the upper right corner of your radio, so it will fit back to dash.


Now you have to decide where to put line in socket and a switch. I choose a free space near cigar lighter.

Using hot knife cut a hole and put a switch in it.




Now we have to connect control wires to +12 and GND. The best way is to use cigar lighter's wires. One wire to the ground(black) and to relay box, other wire to +12(red) and to the switch. One more wire from the switch to control box.


Now put your radio back to dash and have fun!


Here's a video of how it works.

[Dronix]

First of all, please excuse me for my english, it's not my native.
Second, I know, I know, you can add AUX line-in to your radio using some kits. But they all require satellite radio installed, which is not an option for European cars. Anyway, may be someone could find it useful.

So here we go.

A little bit of theory.
As we know, CTS has an amp installed (located on the left of trunk). As I find out, volume controls affects not the radio itself, but controls amp directly. So all what we have to do is to replace sound line with our line-in, and we'll keep all volume controls works.

There are two channels on every mp3 player - left & right, each channel has 2 wires: signal (+) and ground (-). In most cases, both channels has shared ground wire. But, in our car there are two separate grounds (so we'll get less noise).

So everything we need to do is to switch 4 wires (+ -, 2 channels).
The best way to do this is use two relays.

Lets get started

What we need:
1. TR99-12VDC-SB-CD relays – 2 pc. (about $4 each) or similar.
2. Switch - 1 pc, ($1-2).
3. 3.5mm socket ($1-2).
4. Few colored wires.
5. Soldering iron and stuff
6. Piece of cardboard
7. Small plastic box (i've bought one in radio shop, together with relays, for $2).

Step 1. Preparing line-in socket.
Take any 4-wire cable and solder it to your socket. One wire to the left contats, one to the right, two wires to long one (that is common ground).


So now we have a 3.5mm cable


Step 2. Relay box
The best way is to make a circuit board, but I didn't have a tools so I just picked an air freshner made of cardboard.


Now make a holes for relays' contacts


I've put a little schematic on the back of the board so I didn't get confused. Both relays sit in holes.


Take a soldering iron and solder colored wires like this:


After soldering work is done, I put everything in this little box and marked wires.

[2005CTS-V]

Nice writeup!

[JimmyH]

Excellent write-up. I embedded the images and added a link to the DIY thread.

Thanks, and welcome to the forums!

[Kingoftypos]

Nice write up, I didn't read it all because I already knew the fact the amp did all the audio adjustments. But the reason for my post is the fact that you should already have RCA hook ups. They should be located under the center arm rest, or with in it. This because of it being an European car, they obviously forgone the XM radio. Instead, they installed the RCA inputs. At least I've seen it on here with lots of other European cts'.

KOT

How did that air fresher smell like before you screwed holes in it? Lol

[Dronix]

Hey KOT thanks for your note, but I didn't have RCA there. May be there are RCAs on Navi radio? I don't know.. Anyway, nobody knows how to turn them on)

ps. It smelled strawberry)

[JimmyH]

There are also video pinouts on the back of the radio that are not active.

[Tlorenzen]

I know there is a setup for doing this with the xm radio, but can this still be done with the navi head unit or do i need to use the xm way? Seems this would have better quality?

[Ryukhan44]

Hello,
I just finished installing a Scosche IPFMRDS FM RDS iPod Interface in my '03 CTS factory radio. It worked better than expected and very easy to install. The painful part was waiting a month to get it from Crutchfield. Next, Boss 1800 watt amp install.

Ryukhan44

[Beachnau]

Hi Ryukhan 44
New to the forum. I am leaning to purchase the scosche ipfmrds. I do not have xm on my stock radio (2004) cts. Does the wire harness supplied with the unit just plug into a port from the cd changer like the Crutchfield info says? What (red) hot wire did you tie into and the same ? for the white?

Beachnau

[nastymigui]

Great write-up. Useful for those who are thinking about the carputer upgrade as well.

[Tlorenzen]

I know i posted this question before, but in hopes of an answer, does any1 know if that can be used on a navi head unit also? Seems better than the xm round, plus i'd still be able to keep it if i decide to

[oneil]

I really wish i knew how to do all this. Being 18 and having no idea about audio/wireing sucksss!

[X Rolls-Royce]

I really wish i knew how to do all this. Being 18 and having no idea about audio/wireing sucksss!

I earned an Electricity merit badge and an Electronics merit badge in Boy Scouts. I went on to repair pinball machines, video games, jukeboxes, cigaret machines, soda pop machines, snack machines, you name it.

[carrnuttdave]

I really wish i knew how to do all this. Being 18 and having no idea about audio/wireing sucksss!

Every body has to learn sometime!