Hard-wire a Splitter /w USB Inside Your Cars Center Armrest Compartment

Introduction: Hard-wire a Splitter /w USB Inside Your Cars Center Armrest Compartment

About: I always have ideas of making stuff but never actually do. So instead I read other people's ideas and sometimes modify them to a higher standard. I have several DDR pad plans for lit foot panels based on ste...

This is my first Instructable ever! Don't be too harsh if I left something out, I'll happily address it!

For a few weeks, I've been drawing up plans on doing this. I've finally gone ahead and done it. It took a total of 3 hours, making it up as I go.
With proper guidance, it should probably take you a lot less time.

Some of you have been asking: What's the purpose? What does it do?

It's a splitter. This project will grant you 3 cigarette lighter ports and a USB slot in your center console, all without plugging up the original cigarette lighter.
Well the feature highlight for myself, was having a splitter close by to me, the driver, that was both secure and out of sight. This means that if I found out my phone/mp3/whatever was dying, instead of having to reach all the way down to the foot area of the passenger seat to plug it in, I could merely open up my armrest and plug it in there. I could also throw the electronic device inside the armrest so it wouldn't go sliding around my car while charging. Not to mention the random unplugs that came when using the cheapo device as it's manufacturers intended.
After completing the project, I came to realize that it also hides my charging electronics away from would-be criminals who peer into windows looking for a reason to break in.

So +1 for that! (When you have a 200$ window broken so the robber can steal your 35$ mp3 player, you'll agree)

Be Forwarned, I cannot be held responsible for any damage to you or your car in your attempt to reproduce this.
It should be pretty straightforward, but some people find a way to ignore steps.


Here are the tools you'll need:

A splitter /w or without USB :You  don't need to use the same one, but the guide was written with this type
Tin-snips for making the base the perfect size
(8-15$ at your local lowe's or home depot)
Glue (not a gluestick.. we're talking decent glue)
A Soldering Iron
Screwdrivers (Philips)
-One decent sized for your car
-One smaller on for the splitter
Wrench, Socket-wrench (of your car's specifications. mine is 10mm)
The know-how to take apart your car (or a forum, google to find the info)

Electrical tape
Butt Connectors

Step 1: Take Apart the Splitter

Here we get at the innards of this lovely splitter.

1. Take your smaller philips screwdriver and take the screws out.

2. Once inside, remove any more screws holding this contraption together. (might be one on the USB and on the plug itself)

3. Take your soldering iron and detach all the pieces from each other.
(take note what connects to what, especially if you don't have color coded wiring)

Step 2: Take Apart Your Center Console

Now that you've got your splitter apart, it's time to take apart the car.

Get out your decent sized Philips and your wrench.

--This part is different for every car, look up your own on google--

FOR 7th Gen Celica:

On my car, I had to remove 2 Bolts below the carpeting inside the center console's compartment, and about 6 screws.

On my celica, I have to remove the shifter-boot and then pry up  the plastic piece that fits around it (including the cigarette light portion which you must unplug) With that gone, I can get at 4 screws I need gone -2 on the central window controller (which you also need to unplug to remove) and -2 mounting the center console to the dashboard. There were also -2 screws on either side of the center console to remove.

Now I have these pieces taken out:

Shift boot
Ash tray and Cigarette port
Center console including arm rest compartment and cupholders

Step 3: Drill Some Holes and Snip Some Tin!

Now that you've got your compartment taken out, you'll need some holes to wire up your stuff so it looks nice and neat.

This is probably where you'll want to take out your tin-snips.
-I'm assuming that your center console compartment looks something similar to mine. If not, this step may be entirely different and you may want to change it around to suit your needs.
For me, however...

1. Get out that flat metal piece. You'll want to cut it to about the size of the alcove (seen in the picture)
2. When you have it down to the size you want, you can drop it down into the area. (make sure you can get it back out).
3. With it in place, mark the spot on your center console where there's a hole in the metal. This is where you're going to drill your first hole.
4. The next hole will be somewhere lower inside of the compartment, where you want the USB to be.
-Make sure that the wires from the USB are convenient or long enough to reach the part with the splitter

Step 4: Time to Wire It Up! PT1

Here's where your soldering experiences will be put to the test.
Nothing it going to like being soldered to. You have to get around that fact and try.

If you bought the same one I did, it should have a fuse built into the plug. So we're not going to scrap that. If you didn't, well it never hurts to open it up and find out. A fuse will save you if you get a short circuit, so I definitely recommend it.

Anyway, the round part of the cigarette lighter is the ground, while the part inside is the live. (i may have it backward, but for the sake of this guide, i'm going with it. it's pretty straightforward anyway)

1.) get yourself some decent lengths of wire. Hopefully you have two colors of wire. It helps. I have white and black. Use your own judgement based on how long your center console is and how far the wire needs to go to get back to the cigarette lighter

2.) Solder the white wire to the bottom of the flat metal piece. Solder another, smaller, white wire to the flat metal piece. (the shorter will go to the usb so it doesn't need to be long)
Solder these to a point on the surface where it won't get in the way. Because it's underneath, that should be anywhere. But depending on the thickness of your wire, you may want to make it closer to the hole so that the metal piece sits somewhat flush.

3.) Solder the same length BLACK wires to the round pieces. Make in an area that can easily access the drilled hole without getting in the way.
Note, if the round pieces don't fit the way you want them to, you don't need all of them. You can use as many or as few of them as you like. Just cut off the extra with the tin-snips.

4.) Pull the second, smaller, black and white wires through 2 sets of holes to where you wanted the usb to be. This is the simplest soldering you'll do. Touch your soldering iron to the wire and black wires currently there and remove them. Replace them with the new, connected wires of like color/connection (remember what you took off what)

5.) Gather the two longer wires. Solder the wire from the flat metal piece (white) to the tip (springy button-ey part in front of the plug)

6.) Solder the wire from the holes/buckets (black) to one of the metal parts on the side of the plug.

Step 5: Time to Wire It Up! PT2

Now that we have all that done, it's time to actually get some power for this thing. Because we want it to be neat as possible, it's going to be soldered to the back of the cigarette lighter port. This is good and bad at the same time.
It's good because you don't have to see all those ugly cables everywhere.
It's bad because this thing absolutely HATES being soldered to.

If yours is anything like mine, the damn thing is made out of brass. Being made out of brass, it has a very high heat capacity, meaning trying to melt solder to it just isn't going to happen.
You can vary your steps up if you wish, but I found this to work out well.

1.) Take another piece of (white) wire. This piece is going to connect from the loose (white) wiring on the plug to the highest point on the socket, where the TIP would hit on the other side. Look for a piece that's connected to the car's wiring. This is generally a good place to solder to. Just don't block the car from delivering power to it.

2.) And another piece of (black) wire. This piece is going to connect to the outermost side of the socket tube. Look for a place where the car's wiring meets the tube. I soldered my wire directly onto their wiring. If you attempt to solder onto the brass, the wire is more than likely going to come lose.

3.) If you have soldered these wires to the plug as well as the socket, do so now.

Next up, we'll do some gluing.

Step 6: Glue Down Your Necessary Parts

Now that all the wiring is done, it's time to make it look good.

1.) Put some glue on the bottom of the metal plate. Pull the (white) wires on the other side and help it onto the spot you plan on mounting it with your fingers. Make sure the wires are out of the way.

2.) Due the same for the buckets and the (black) wire. Apply glue to anywhere where it will be touching a wall. Make sure that the wire doesn't touch the other wire and that the buckets don't get so low as to touch the metal plate. Generally, you'll want them roughly an inch or so higher. (look at a plug, these buckets are where the outer portion of the plug would rest)

3.) Depending on the usb portion, you can either choose to glue or mount with screws. After doing so, I covered it with electrical tape to prevent anything metal ever shorting it. Be creative with this part, just don't be stupid? :) If you screw it, make sure the screw is mounted with a non-conductive washer.

-Make sure to use something to hold them in place while they're drying. I used electrical tape.

-Also, pay attention to the warnings on your glue. If it says keep it in a vented outdoors, it's probably not the best idea to shove it right back in your car for a day. Don't subject yourself to fumes.

Step 7: Testing Process!

Before connecting it to your car and turning it on, do a once-over and make sure you have no shorts.

Make sure to cover any exposed wire. I use electrical tape to satisfy that.

For this part, I used a multimeter. It's not exactly important to the process, but I found out that on my USB portion, I had some stray solder that would have caused a short. So do your once over and make sure everything is working fine, ESPECIALLY IF YOU BYPASSED OR CHOSE AGAINST A FUSED CIRCUIT.

Once you've gave it a look-over, go ahead and plug your cigarette lighter portion back in.
Didn't blow up? Good.
Go ahead and plug something in and check that it actually gets power.

If everything looks good, go ahead and put your car back together!

At this point, I decided to drill a bigger hole and run a 3.5mm stereo -> RCA cable to the back of my Head Unit so that I can leave my phone charging inside the center console and hear it ringing on my speakers. (Clearly wouldn't work if your phone didn't have audio out)

Thanks for reading!

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    3 Discussions


    8 years ago on Introduction

    How did it hold up? I'm thinking of doing the same to my celica!


    Reply 8 years ago on Introduction

    Not bad at all. Just make sure that you securely glue it in. I was a bit impatient and needed to get my car back together, so my glue job was a bit inadequate and it eventually came apart. I've been meaning to re-glue it, just no time!


    Reply 8 years ago on Introduction

    Haha what sort of glue did you use, so I'll know to avoid it? I was concerned about the reliability of the splitter and its fuse, but if it's held up this long, must be good! I'll buy the same one as you since the ebay item is still up.