So I wanted to upgrade my stereo system but I wanted the "works;" or at least the necessary items I would need in my every day travels. My boy has a Infinaty M35 and the bluetooth phone set up, where the car stereo cuts off and play's your phone call through the speakers, was an immediate draw. I also wanted Ipod connectivity where I managed my music selection through the head unit and not the Ipod itself. I also wanted an AUX input in case some person had an mp3 player or something and he/she wanted me to hear through some kind of audio source (mp3 player, mini disc, etc). Also needed were mp3 CD and CD-RW playback from the unit itself. I settled on the Pioneer DEH-P7900BT and the Pioneer CD-1200 Ipod cable. I also wanted to install a sub and amp as well so this became the ultimate audio upgrade for my little e36 sedan.

Before I begin here's what you'll need to know how do do so scour these DIY instructions and familiarize yourself with these first:

1). Removing the back seat and accessing the trunk from the rear arm rest.
2). Removing the front arm rest counsel (don't need to know how to remove the arm rest itself, just the surrounding counsel.
3). Removing the shifter trim.
4). Removing the sunglasses cubby.
5). Removing the old/factory stereo.
6). Removing the climate control unit.
7). Removing the computer.
8). Removing the glove compartment.
9). Installing an amp and sub. (The instructions are usually with both the amp and sub but this DIY will help you thread the wires to the head unit instead of using a hi/low converter to connect to the rear speakers).
10). Installing a head unit i.e. know what wires connect to what.

Once you're comfortable with these steps and have done them, you may proceed on.

You're best friends during this task will be a wire hanger and patience.

Probably the hardest step in this is getting the wires from the trunk under the back seat, hidden under the carpet and back up through the center counsel. Sorry but no amount of searching provided a clear DIY on this or any other site to accomplish this task. Please correct me if I'm wrong but I couldn't find anything. But a lot of board members help me figure this out so thanks to you guys.

Pic 1 shows the center counsel removed. If you'll notice I used a wire hanger and threaded it all the way to the back of the back of the wall under the rear seat. Pic 2 is a close up of the curved end of the hanger. Now Pic 3 shows the back end of the hanger coming out of the rear end of the carpet but this is not easy. What happens is that the center hump (best way to put it) runs right into the back wall which is carpeted. In order to get the wires to be hidden I had to cut a hole into the back carpet pretty much dead center behind the hump itself.

Pic 4 shows how the hump mets the back carpeted wall. Pic 5 shows the hole with the hanger coming out the other. Once you've threaded the path for the wires to travel through, I'd curve both ends so that you don't pull to hard and pull the hanger out from the other end.

I choose to pull the RCA cables, power on, and bass control wires separately. These wires were big so doing them one at a time just work easier. Pic 8, 9 and 10 show the bass control wire which is pretty much the same as a network wire which you connect a computer's ethernet cable to a dsl model/cable model. You will notice that the end is taped up. This is to protect the plastic clip from breaking off. Once I taped off the clip, I just taped it to the hanger wire and pulled from the center counsel until it come up from under the carpet. You'll have to pull on both the carpet on the rear wall and fiddle between where the wall and hump meet to help the wires along. Repeat for the RCA cables and the power on wire.

Here are more pics of the individual wires as well as close ups of the rear wall and the hump. I have to stress how patient you must be when doing this parts as well as being careful the the hole in the carpet is hidden behind the hump.

This first pic shows my hand helping along the threading of the cables from the rear wall under the carpet along the hump. Ok time for some clean up. I bought my e36 used and I did a nice job of cleaning it including taking out the seats and getting underneath but I never took out the center console and being that it's a '98, 10 years of use, a lot of filth builds up. I took this time to clean the carpet as well as the console thoroughly. Now time to run the wires up to the head unit. you gotta take out the shifter trim. My car's an automatic so manual owners you'll have to make adjustments where allowed.

With all the wires through, I taped the ends together. BUT WAIT; THERE'S MORE!!!!!

Here's the thing; I have to start threading the Ipod cable with the RCA cables and the power on wire since they're all going the same path to the head unit but the amp control cable doesn't. Instead I'm going to have that wire come out the center console and hook up to the control dial. Similarly, I decided to hide my Ipod under the cup holders. So where one cable ends, another begins.

Using the conduit covering I started to wrap all the wires into it just to give it a neat appearance. Another best friend on this project are plastic ties. You can see from this round of photos that I threaded the wires through the shifter column.

The second pic shows the aux input set up. I used the blanked spacer and drilled a hold, cut the top off and hot glue the input (I don't remember the specific size or the correct name of the particular piece but it's stereo in (female input with a male output) I took hot glued it into place. Now mind you, I didn't have to correct cable so I had to bastardized a connection. For this particular model, the Pioneer head unit's primary aux input is a simple input that's basically the plug on the end of a standard set of stereo head phones. So find basically stereo head phone extension wire and you'll be good. But being that I didn't feel like purchases extra parts from Radio Shack, I just took a bunch of RCA inputs and put something together. By the way, I started to pick up speed but the last pic is proof that you must take your time. So I had to take a crazy glue break to repair the cigarette lighter light holder.

TAKE YOUR TIME.

Well the pics pretty much illustrate what's next. With the old head unit out it's time to set up your mic for the blue tooth connectivity.

I had to thread the mic behind the glove compartment, then take off the passenger trim strut (don't know the name but look up the headliner removal DIY and it tells you how to take out this brace). You don't need to remove the headliner but you'll need to remove parts of it, one being the passenger side vanity mirror, and the mirror light. This is where your wire hanger becomes your best friend. Tape up the end of the mic and thread it through these small places until you get to the panel where the sun roof switch is. Now lets' hook up the stereo first, make sure everything works fine.

Now here's the thing: using the sunroof panel to hold the mic in place works well but on some calls and especially if I'm talking to someone using a blue tooth ear piece, on my phone, the mic seems to be too far from the driver's voice and I have to elevate my voice, nah, I have to yell. When testing the placement of the mic called a land line and it worked fine, sound was clear, the person I called heard me clearly. But one night driving to the club, I called my boy and he's using his blue tooth ear piece and I was yelling and he barely heard me. Ultimately, if you can and feel comfortable cutting into the headliner fabric then put the mic closer to the driver. The reason I have no regrets is because my friend seems to be the only person that has a hard time hearing me. I leave it up to you.

Let's get to the rear of the car for a sec.

Take out the rear center armrest, pull down the leather flap and see the rubber dampener and the metal plate. If you pull up slightly on the rubber dampener you'll expose a small hole that gives you access to the trunk, once you take out the carpet panel in the trunk itself.

Send the wires from the rear carpet wall up under the leather seat bump, behind the leather flap, into the hole to the trunk. Please look at the photos for details.

Put everything back, the rear seat, the center console, every thing except the cup holder and the front ashtray.

Go to the trunk and hook up your amp and sub. Plug up your ipod, plug up the amp control to the cable (you can remove the black tape that protects the plastic clip) and check your sound.

With everything tuned well, time to set up everything.

I tuck the Ipod under the ashtray. The head unit automatically charges the ipod when the car is on. I only need to remove it when I want to add music and I doubt a thief will pull up the center console unless they see you put it there. I thread the Amp control cable through the ashtray and connect and disconnect it each time I get in to drive. Put everything away.

This will work fine for now but this summer I plan on doing a more cleaner fit ment.

Clean up and drink a shot of Hennessey.

Enjoy!

Anyone knows how to get the DIY unto the DIY thread?

Wow. That was harder than I thought.

For the mic, have you considered putting in the A pillar? That placement looks it might get a lot of ambient noise.

Well done. :thumbs up:

Great writeup. For my subwoofer setup, I ran the cables through the ski pass, under the rear seat, under the carpeting on the driver's side rear passenger area (under the plastic panel near the door), under the B pillar carpeting, under the driver's side plastic door trim panel, under the driver's door seal, under the driver's side dash, behind the climate control unit, to the head unit. All of 5 minutes, and completely hidden! I agree, your way is far more professional, and is something I'd undertake if I wanted a more permanent setup.

Glad to have you in the forum, as you seem really knowledgeable about this type of stuff!

Anyone knows how to get the DIY unto the DIY thread?
I would suggest sending a private message to one of the moderators on the board so that they can move it. It's a great thread!

Wow. That was harder than I thought.

For the mic, have you considered putting in the A pillar? That placement looks it might get a lot of ambient noise.

Well done. :thumbs up:

Thanks for the compliment. You know, I never considered the A-pillar. Yet another option. In my friends M35 it's located directly above the driver seat. I didn't feel comfortable cutting into the headliner so I opted to only cut into sunroof control's panel. I will give it time and see how it plays out. My only concern is during the summer time with my sunroof open, what kind of noise I'll get.

Great writeup. For my subwoofer setup, I ran the cables through the ski pass, under the rear seat, under the carpeting on the driver's side rear passenger area (under the plastic panel near the door), under the B pillar carpeting, under the driver's side plastic door trim panel, under the driver's door seal, under the driver's side dash, behind the climate control unit, to the head unit. All of 5 minutes, and completely hidden! I agree, your way is far more professional, and is something I'd undertake if I wanted a more permanent setup.

Glad to have you in the forum, as you seem really knowledgeable about this type of stuff!


I would suggest sending a private message to one of the moderators on the board so that they can move it. It's a great thread!


Thanks for the good words. Your ways seems a lot more complex then mine. It took me about 6-8 hours total with amp, sub, and everything. it's a big job but well worth it.

I tried to get under the plastic door panels and cracked the passenger side front panel. I opted for cutting into the carpet because it was a no mess no fuss operation.

man, thanks for this, im about to set up my system and have been posting up for soimeone to show how they wired their stuff, and looks like you did what i was looking for =)
nice clan job on the set up!

man, thanks for this, im about to set up my system and have been posting up for soimeone to show how they wired their stuff, and looks like you did what i was looking for =)
nice clan job on the set up!

Thanks man. Wire hanger and plastic ties are your friend, and take your time, I can't stress that enough.

Great DIY!

I have my recently aquired '94 325i convertible powered down for the winter, replacing all light bulbs in instruments and switches. Along with a bunch of other lights, the light on my climate control is out, so I can't see the controls at night. I have looked at the TIS, and it says to run a feeler gauge under the unit and pull it out.

I have the radio out, and have about worn out my feeler guages sliding them around under the climate control unit, so...really...how do you get the climate control unit out?

I see that you have it listed in your steps, but I have not been able to get the bugger out.

HELP!

Great DIY!

I have my recently aquired '94 325i convertible powered down for the winter, replacing all light bulbs in instruments and switches. Along with a bunch of other lights, the light on my climate control is out, so I can't see the controls at night. I have looked at the TIS, and it says to run a feeler gauge under the unit and pull it out.

I have the radio out, and have about worn out my feeler guages sliding them around under the climate control unit, so...really...how do you get the climate control unit out?

I see that you have it listed in your steps, but I have not been able to get the bugger out.

HELP!

Pull out the turn dials and knobs, you'll figure it out after that. :)

man you guys are genius!!