So I've been playing around with my head unit trying to make an input to it.

My first idea was to connect it in like it was a CD changer (my changer was already broken). However after blowing a fuse (stupidly). I figured out the head unit has some way of "knowing" the CD changer is connected. I didn't try really hard but I couldn't figure out what it was that switched it on to allow input from the changer.

So from there I decided to attack my tape deck (also broken). I found where the head of the tape deck was on the radio's circuit board and figured out what was the speaker channels and what was the signal ground.

What I didn't think of at first was the fact that a tape puts out a LOT less electricity than an MP3 player so when I initially put it in it was really "hot". It distorted even at my MP3 players lowest volume. So I had an inline volume control for a set of old headphones laying around and I put that on after the MP3 player and with that at the lowest volume it works pretty much perfect. There is a little bit of static however (way less than any FM transmitter I've used) I did leave the tape deck head hooked up and I think that is attributing to some of it.

So my idea to eliminate the in line volume control initially was to put a few resistors on the line however I had an old tape deck adapter kicking around and I took it apart. Inside there was exactly what I needed except on a neat little circuit board. I'll hook that up tomorrow and it should be perfect. I'm also going to unhook the tape deck head.

One of the advantages I have is that my tape deck is broken to think there is always a tape in it which is necessary for this to work. Although if one were to use a tape deck adapter for the project they could also use the tape part as a dummy so the radio would think it had a tape. You could take out the wheels on the tape so it would be silent too. The only real advantages to this over a tape deck adapter are that you could run the wire cleanly to the armrest or something rather than having it stick out the tape deck. The tape deck as I said also wouldn't make any noise. The sound quality is likely to be a little bit better too due to the direct connection.

This may have been done before but I couldn't find a write up for it. So since I have to take everything back apart tomorrow I will take some pictures and do a proper write up on it.

EDIT:AUX input DIY

DISCLAIMER: When doing this mod there is the risk of damaging your radio. I would suggest only to attempt this mod if you have experience soldering and working with electronics.
With that said if you follow the procedure correctly there should be no problem. I also apologize for the bad pictures but my camera is on its way out.

Tools: Soldering iron, wire strippers/cutters, Phillips and flat head screw drivers, Multi meter and maybe a lighter.
Materials: Solder, a good wire with plug headphones or tape deck adapter, resistors or and inline volume control (see image 6A and 6B) and electrical tape.

1. The first thing you need to do is remove your radio. This really should be done with the correct tool however I managed to do it with a flat head screw driver. I popped my faceplate off and then moved the small metal tabs on the bottom corners of the radio inward while pulling out on the radio. (This is easier if you have two people). Be very careful if you don't have the proper removal tool because A) the plastic on and around the radio is easy to damage and B) the radio's circuit board is unprotected right about these tabs.

2. Bring the radio to an environment where you have very good light and an open workspace.

3. Open the radio (See figure 1A below). You will be opening the radio from the bottom and to do this you must remove the two screws located on the back bottom of the radio (all the screws on my radio were very tight so use caution and the proper screw driver so as not to strip them). With the screws removed the metal plate lifts up and back to remove it. If necessary gently pry the sides loose with a flat head screwdriver.

1A


4.Locate pin 5 (See image 2A). With back of the radio facing you look at the top right. You should find a pin labeled "5". This is the ground. Above Pin 5 are pins 3 and 4 however they are not labeled. Pins 3 and 4 are the left and right channels.

2A


5. You will need to know what wires on your headphone/ tape deck adpt. cable are speakers and ground. Strip the wires (if you have a hard time with the small wires sometimes using a lighter you can melt the plastic a bit on the end and then it is easy to pull off). Often the wires will be black, red and white or red, white and non-insulated. The red and white are typically your speaker wires however whether or not this is the case or you think you can tell you should check. To check you will use your ohm meter to test across the wire. The plug is as follows: the inside section is the ground, the middle is a speaker and the outside (or end) is a speaker. (See image 3A)

3A (Top orange circle are speakers and bottom blue circle is the ground)


6. You must now carefully solder your two speaker wires to the circuit board (Here is where you would wire in your resistors as well however I used a volume control). Solder one wire to pin 3 and the other to pin 4. Then solder the ground(s) to pin 5. (See blurry and unhelpful image 2B)

2B


7. Put a piece of electrical tape on the circuit board under the edge of the ends of the wires you just soldered. Then make sure the wires are well separated and put tape over the wires holding them down to the first piece.

8. Now run the wire out of the radio somewhere. I ran it above the antenna jack and bent up the metal tab on the cover so as not to damage the wire. Before you put the the cover back put a couple pieces of tape on the wire to hold it to the circuit board to hep prevent it from being pulled out. (See image 4A).

4A


9. Put the cover back on.

OPTIONAL: This section is optional and may or may not be worth it. I did it because my tape deck does not work anyway and I think it may cut down on static. If you want to keep your tape deck usable skip to step 16.

10. You will now remove the top cover by taking out the screws and lifting it up much like the bottom cover.

11. With the cover open and the back of the radio facing you locate the tan tab/plug that is wired to the tap decks head. (see image 5A)

5A


12. Unplug this. (See image 5B)

5B


13. Tape up the contacts on the plug.(See image 5C)

5C


14. Then tape this plug up somewhere so it's not banging around in your radio. (See image 5D)

5D


15. Put the cover back on.

16. Plug the radio in and test across your wires on the plug to make sure you don't have some weird short or 12v's feeding back into it so you don't kill your MP3 player. Test it and make sure it works before you put it all back together. If you are using an inline volume control turn the volume on it all the way down (because this is your make shift resistor). Turn your mp3 player volume down as well. Now turn the radio on. Put it on "tape". Now slowly turn the volume up on the mp3 player (with mine I keep it turned all the way up). If you need to turn the in line volume control up VERY VERY slowly. If it works sweet if not... well you may have done something wrong.

17. Now you need to figure out where you want to run the wire. I took out my ash tray console (I don't smoke). On the back of the unit there is already a hole behind a clip for a plug junction. I took this hole and drilled it out a little bigger. With the hole bigger take out your actual ash tray that clips in and run he wire in there. This is where I put my inline volume control (see images 6A and 6B) and keep my mp3 player. (see images 7A - 7C for the final product)

6A


6B


18. Now put everything back together and you have your final product. (see images 7A - 7C below)

7A Convenient


7B Clean


7C Concealed

 

very nice, i havent' seen this done actually. hurry with the writeup lol

 

Better make sure you don't overheat things. I dunno if I would be comfortable digging around in my tape deck.
If your deck does work,
for $9.99 buy a cassette-to-headphone jack hookup.

 

I bought one of those dice modules, it works amazing, you can switch through songs and albums through your headunit, it charges your ipod and the sound quality is amazing. I got it used for $30 shipped on ebay

 

Yeah I wouldn't do it if you don't feel comfortable with that sort of stuff.
I just had nothing to loose with my radio because it was mostly broken anyway. I figured it out though.

 

Finished it! DIY up.

 

Nice Rick, freaking sick idea!

Dudeman

 

nice write up, but not worth the time and effort, I just have a phatbox 20gig hard drive installed where my cd changer was and it works great.

 

my stock head unit wont work at all(not becuase of diy aux input, never did this) i checked the fuse for it and thats fine any ideas why its not working?

 

How is this hooked up? Can I switch through songs and albums with my STOCK headunit?