Hey everyone - since I just completed an aftermarket audio installation in my 04' I thought I would make a tutorial. I think the information can be readily found through searches, but sometimes I ran into a situation that I couldn't readily find information about. It's also worth noting I have never so much as installed an aftermarket radio, so this was a completely new experience for me.

First and foremost - for those without experience... it is not as easy at it seems with our trucks.

I likely won't get it all typed up in one sitting - but I will continue to edit the post until I feel like I've covered everything I ran into while installing new products.

Starting - unhook the negative terminal from the truck battery*****

1. Stock Radio Removal

A. Removing stock head-unit: This one is easy. Crutchfield sells two tools that will do the trick, but you can also find hanging file folders (you know.. the green ones that used to be prevalent in offices with the metal holders). The file folder route gets the job done, but you need to find a file folder that has a slim metal holder (the newer ones are more re-inforced and do not fit). Look for a flat metal holder. Remove one from the file folder - cut it in two and insert both ends into the two tiny slits near the top of the stock radio. Once you hear a click or they seem to lock into place pull straight out. It may take a little effort, but it should slide out after you get it going. Remove the connections at the back of the radio and you have successfully taken the stock radio out.

B. Remove the metal trim previously holding the stock radio in place. I did this by essentially bending the bottom portion of the metal frame up (the frame has two pieces that connect at the bottom. On mine they connected about an inch or two from the farthest right portion of the bottom). Once you've bent it up you can wiggle the frame out and bend it back so you could replace it should you sell your truck.

2. After-market Radio install
A. I bought my radio from Crutchfield. They recommend using an after-market wiring harness to connect the existing speaker connections to the after-market wire harness (I used the Metra 70-1786) and the subsequently installing the after-market wiring harness to the new radio. In theory this is easy. However, problems arise when you see that in order to do this you need a line-out converter (I used Scosche SLC4 - it's blue).

B. I personally would not re-wire all new speaker wires. Once I got everything installed with the after-market harness and the Scosche SLC4 the audio worked great.

C. Here is where problems arise. The existing speaker wire, after-market wiring harness, and the Scosche line out converter will NOT fit behind the after-market radio once installed. I tried for hours and it will NOT fit. Save yourself valuable time and move on the to the next step.

D. The Metra wire harness (I had it pre-assembled by Crutchfield) will come with unnecessary wires connected to it. I had an issue with my radio flickering when I would turn on my headlights. I cut the ORANGE/WHITE wire on the harness and didn't use the connection - once I did this the flickering went away completely. Orange = video (you would want to leave this if you have installed an after-market back-up camera). If you don't have a backup camera (like me) I just cut this wire near the harness and wrapped it in electrical tape. Reduces the mess and provides a little more room. The PINK wire is to be connected to the emergency brake if you purchased a radio that can also play DVDs. I purchased the Axxera 7' DVD monitor. I bypassed the emergency brake requirement by grounding this wire. Shhh. don't tell the authorities. The BLUE/WHITE wire is for amp power. If you want to install an after-market subwoofer/amp combo you would tap into the BLUE/WHITE wire on connecting the Metra wire-harness to the stock radio wires. I used a posi-connecter to tap into this. Super simple. The posi-connecter has three pieces. A middle, and two end caps. Unscrew the larger top portion and place it over the wire you'd like to tap into and then screw the middle piece into the top portion. The middle piece has a little needle that will pierce the wire. The littler bottom portion has a hole through it. Slide your remote wire from the amp (should be solid blue) through the hole and into the middle piece. Then screw the bottom piece into the middle piece. You're done wiring your amp now. ***AMP - you will want to connect the positive red cable to your battery - punch a tiny hole into the rubber gromet at feeding wires from the engine bay into the vehicle located on the left side of the engine bay up against the firewall. Feed your red wire through the hole you've made and run it along the bottom portion of your truck to wherever your amp will be located. Feed your BLUE remote wire from the amp along this same side up to the glove box and into the radio bracket. The RCA cables from the subwoofer to the radio unit should run alongside the opposite side of the truck to the radio unit.

E. Subwoofer sound: The harness and converter will also come with connections for an aftermarket sub or external video monitors. You would run the RCA cables from the subwoofer along the left side of the truck up through the fuse panel under the steering wheel into the radio bracket and plug the rca's into the correct hookup for the receiver. They should come labeled and it will be easy to see which one to use. Mine were green. To GROUND the amplifier I lifted up the rear seats all the way and unscrewed a nut connecting the seats to the chassis and place the ground wire on the bolt and re-screwed the nut. I tested the voltage coming to the amp after doing this and found I had more than 12v going to the amp. ***You can also buy a self-tapping screw and drive it directly into the chassis and connect your ground that way. I may re-do this in the future, but I don't have to.

F. Scosche maintenance: make sure your speaker wires are firmly locked into the correct positions at the top of the line-out converter. Mine came with the positive green wire for the rear left speakers loose and when I didn't hear sound coming out of those speakers I found that was why. Make sure you've also turned the gain controls on the scosche all the way down (-). Once you've made sure the connections are sound. Plug everything into your after-market radio BEFORE placing the radio into the bracket. Re-attach your negative terminal to the battery, power on your vehicle and turn the radio unit on. This is when you will test your speakers (I tested mine independently by moving the fade and balance to the different speaker quadrants. If sound is coming from all speakers you've done a good job thus far. *****The Scosche manual says to try the sound at the "Factory Amp" setting (a little black switch on the side) I found that I didn't get any sound utilizing that position (nor the common ground connection option) - I switched it to "Line-Out" and sound came through in spades. Once you hear something now you should start adjusting your gain levels to get the proper sound coming out of your speakers. Ideally you should set all the gains for the top to the same level and all the gains for the bottom to the same level. I used a tiny flat head screw driver to do this.

G. Mounting the after-market radio: This was a B****. Save your time and go ahead and remove the AC control panel from the dash. This is easy once the stock radio is out. Put your finger in where the radio was on both sides of the AC panel and depress the metal tabs and slide the AC panel out. You can leave it hooked up, but put it down and out of the way. The Scosche is going to go behind the AC panel. The AC panel wires are connected in a bundle behind where the panel fits when mounted. There is a white zip tie fastening the cables to a middle portion of a metal bracket. I snipped the zip tie and slid the Scosche up under the wire bundle there. You need to take the existing speaker wires and move them all the way to the right portion of the radio tray and feed the wires connected to the Scosche up through the right portion to connect there. This minimizes the wire bundle and will let you install your radio easier. The portion that connects from the Scosche to the aftermarket receive will go left through the AC panel slot and then up into the radio section and then out towards you when looking at it. You will not have a bunch of give in the wires but that's ok. Once you have everything with the wire-harness and the Scosche installed I grabbed the after-market radio - installed the metal bracket onto the radio and moved the radio up near the bracket. I inserted the wires to the back of the radio and then pretty FORCEFULLY pushed the radio/metal bracket into position. This was the only way I could get everything sit flush with the dash. Once this the radio is installed you can replace the AC panel. Congrats - you just saved at least a few hours trying to jam everything into place.

H. Now that the radio is installed - turn your vehicle back on and test for white-noise and interference. My radio puts out a lot of white noise when it is installed, so I re-adjusted my gain levels to minimize the noise. Kind of a pain, but if you can remove the AC panel while the radio is installed you can get to the Scosche fairly easily and not have to un-connect everything to do this.

3. Speaker installation: I had the Hi-line system (Alpine radio unit - once removed you can see)(Philips speakers) The composition of the speakers is as follows: A Frame = Tweeters; Upper front door = Mids; Bottom Front/Back = Mid and Lows; Upper read doors = Tweeters). For purchasing I bought 6 1/2" speakers for the bottom front and rear doors and 3/4" tweeters for the A frame and rear uppers.

A. The doors all have screws in the rubber handles (2), behind the metal door handle (1) and some screws along the bottom plastic portion of the door (mine didn't have screws in every position, but you will be able to see where they are.

B. Once the screws are removed - get a metal pry and place it in-between the door panel and the metal portion of the door. Pop out the door panel along the top, sides and bottom. Push the lock out of its slot in the door and unclip the speaker wires. The bottom speakers will remain fixed to the door panel and there will be more screws to unscrew to remove the bottom speaker. The top speaker twists and comes out of its mount.

C. Dyna-mat or sound deadening material. I decided to line the door panel with sound deadening material first. It seemed to me to be much simpler and cleaner than lining the metal part of the door. However, there are large enough cavities to also place sound deadening material near the bottom of the door behind where the speaker sits.

D. After-market speakers. I DID NOT REPLACE THE MIDS ON THE FRONT DOORS! I couldn't find an option and they sounded fine to me anyways. Once you've unscrewed the bottom speaker from the door panel place your after-market speaker in its place. You will likely need to grab a 1/8" drill-bit and drill new holes for the speaker. It's easy enough.

E. Connecting after-market speakers to the existing speaker wires. I purchased a wire-harness from Crutchfield. It didn't fit... Shocker. I cut the wires just behind the harness that would connect to the stock speaker harness, stripped the wire and used posi-connecters to tap into the existing speaker wires. This isn't too hard. Just make sure you're connecting positive to positive and negative to negative. I believe the positive wire in the front bottom speakers was brown/red. I'll edit when I get home.

F. Replace all screws and re-install the door panels. You should be done here. If you are replacing the tweeters in the rear door just pop the speaker out of its mount and mount your new speaker and connect to existing speaker wire via crimping or posi-connecters.

G. The rear cargo speakers are going to be removed and installed in much the same way - however the tabs connecting the panel to the cargo door are crap. They will break when you remove the door and you may want to purchase a set before removing the panel.***

H. A Frame Tweeters - I could only find one model that "fit" in the stock location (JL audio). I didn't purchase that model. Instead I removed the A frame by prying and disconnected the speaker wire. I removed the foam insert and placed the tweeter in the existing location once the stock tweet was removed (simple turn the speaker so that you can pull it out). Here you can either mount with a metal mount, or fix the speaker to its location with electrical tape. It doesn't look good, but enough electrical tape should secure it well enough. Instead of re-installing the foam into the A Frame I just placed a few strips of sound deadening material on the plastic. The after-market tweeter will likely come with a cross-over included. Just connect the cross-over wires with the aftermarket Tweeter, secure the crossover to the A frame (I used electrical tape) and then connect the crossover to the existing speaker wire using posi-connecters or crimping). Now just replace the A Frame pillars.

CONGRATS! You've just installed a new radio, speakers, and/or amp and sub. The absolute hardest part of the installation is getting the radio to fit in the slot. There is a metal bracket back there that makes this extremely hard. Super frustrating.

I'll post color codes for the stock speaker wire, Metra Harness and Scosche line-out converter later this evening or tomorrow. The good news is you will learn way more than you ever wanted to know about your car audio during this process. The RAVE manual was instrumental, but I will update this with the colors and you likely won't need it.

If you find that you are getting too much interference with your radio you can ground the wire coming from the Scosche converter. It was overkill, but I removed the center console and found a screw going into the chassis towards the back of the console near the rear seats (under the middle bucket) to ground the radio wire and the parking wire). I'm positive there is an easier way to do this, but I couldn't find an acceptable grounding point on my own. I feed the speaker wires from the ground bolt through the console up under the left side of the console through the compartment under the steering wheel and into the radio compartment.

 

UPDATED COLOR CODES and Scosche Line-Out Converter Information:

Discovery Speaker Wires:
B - Black
G- Green
K - Pink
LG - Light Green
N - Brown
O - Orange
P - Purple
R - Red
S - Gray
T - Transparent
U - Blue
W - White
Y - Yellow

The speaker wires may have two colors - the outer color will be designated first and the middle color second (i.e. a Blue and Black wire will be coded UB, a Black and Blue wire will be coded BU).

Metra Harness 70-1786
Red = 12 volt
Yellow = 12 volt constant
Black = ground
Blue/White = Amp Turn On
Orange/White = Dimmer
White RCA = Left Front Speakers
Gray RCA = Right Front Speakers
Green RCA = Left Rear Speakers
Violet RCA = Right Rear Speakers

Scosche SLC4
Input Hookups (A1-A8) There are positive and negative hookups next to each other
A1 = right front positive
A2 = right front negative
A3 = left front positive
A4 = left front negative
A5 = left rear positive
A6 = left rear negative
A7 = right rear positive
A8 = right rear negative

Metra -> Scosche hookup B inputs
B1 = right front positive
B2 = right front negative
B3 = left front positive
B4 = left front negative
B5 = left rear positive
B6 = left rear negative
B7 = right rear positive
B8 = right rear negative

The Scosche (blue plastic piece) will connect the input wires to an adapter that will hookup to your after-market radio. The Output connections will go to the Metra harness and the metra harness will connect to the existing speaker wire harness. From stock to after-market you will only use two of the stock adapters (there are three total). I believe the ones you will use are Gray and Brown in color and the yellow one will not be used (these are the plastic adapters not the wires themselves).

The Scosche also has RCA hookups near the output hookups. When looking at the Scosche converter face on they will be (From farthest left to right): Right Front, Left Front, Right Rear, Left Rear).

 

Using the Discovery color code above here are the speaker wires from factory:

A Frame Pillars:
Left - YB = negative; YK = positive
Right - RB = negative; KB = positive

Front Mids (upper):
Left - KB = positive; RB = negative
Right - KB = positive; RB = negative

Front Lows (bottom):
Both sides: RB = positive; BK = negative

Rear Tweeters and Rear Lows:
Both - BG = positive; BU = negative

Rear Cargo:
Positive connections are RB and WB negative are RB and NB

 

 

 

 

if you get a head unit that has line-level amplifier outputs instead of speaker outputs, wouldn't you be able to skip the scosche adapter entirely?

 

 

 

hypothetically. but i'm assuming that the original unit puts out line-level signals to the amplifier under the driver's seat (and i think there's also a sub amp in the rear door?). connecting an aftermarket line-level unit to the same amp(s) would eliminate the need for the scosche piece.