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Government Approved
363 Posts
Discussion Starter · #1 ·
Warning #1:
This is a Do It Yourself (DIY) and therefore I will take no responsibility for any damage you cause to your vehicle; either from modifications or by driving with the driving aids turned off. Always wear proper safety equipment like safety glasses, gloves, air respirators, and etc. when performing any work or customizations. Use your best judgment when driving with the driving aids off.

Difficulty: 6… for proper wire selection in step #7.
(1 = Air Filter replacement, 10 = clutch replacement on a Lancer Evolution)

Estimated time: 2-3 hours

To install a SPST (on/off) rocker switch that disables the ABS/TCS/VSC driving aids from inside of the car.

For those who feel comfortable driving without driving aids, the one of the methods to disable the Antilock Braking System (ABS), Traction Control System (TCS), and Vehicle Stability System (VSC) is to remove the Green 40A “ABS” Fuse from the engine compartments fuse box. The process of getting out of the car, opening the hood, and removing the fuse can be rather tedious and risks damaging the plastic around the fuse.
By installing an interior rocker switch that simulates pulling the fuse, the driving aids can effectively be disabled, without the added inconveniences. This will be performed by tracing the wire that comes FROM the fuse, and installing a single-pole-single-throw (SPST) rocker switch, mounted on the center console.

Warning #2:
I can’t stress enough the “For those who feel comfortable driving without driving aids…” part of the introduction. If you have driven older cars in the past and do not like driving aids, then that is fine. However, if this is your first car and haven’t had a chance to test your abilities at a rallycross or at least open/cleared-out parking lot, then I would at least hold off on this modification until you feel comfortable driving without them. They are there to protect you and others when driving around on the public roadways, in case you lose control of the vehicle.
Personally, I leave them on for most of the time, and ESPECIALLY when I am transporting anyone other than myself in the car, or lots of weight.

Tools required:
10mm socket + box head wrench
Large Philips head screwdriver
Skinny regular screwdriver
16 gauge wire, usually comes in 24’ lengths
Heat shrink
Female 14-16 gauge connectors
Wire snips
Wire insulation remover
Soldering iron (100W+)
Heat gun, hair dryer, or lighter (for heat shrink)
Electrical tape
Dremel or other means of cutting plastic (for rocker switch install)
Sharpy or paint-pen.

1) When removing items from the car, always use patience if the part does not come off right away. Chances are that there is an additional fastener (screw, bolt, clip, etc.) that still needs to be removed!

2) Remove the front bumper. Place a towel or other large soft blanket in front of the car. There are 3 clips (insert screwdriver into slot and twist) on top of the grille, 2 10mm screws on top of the bumper and 1 clip, and 1 10mm bolt in each fender well where the fender meets the bumper. The whole assembly can then fold down onto the blanket, to protect the paint (don’t worry about the plastic fender liners, they can bend!)

3) Remove the driver side (right) headlight. There are 4 larger Philip head screws that also accept a 10mm socket. Carefully pull up on each mounting tab to remove it from the plastic clip. Disconnect the 2 wiring harnesses.

4) Remove the battery. My pictures show that the battery is installed, but removing it will not only give you more room to work with, but also prompts you to disconnect the battery. There are 2 10mm nuts holding the battery down (a ratchet box head will help here), and the 2 rods hook in underneath. Make sure you hook these back up! A loose battery is very dangerous!
4a) Disconnect the battery.

5) Unbolt the main fuse box. There is a 10mm nut and 10mm screw holding it on. Carefully pull it away from the fender.

6) Disassemble fuse box. The top (black part) comes off with 1 large clip. The bottom (white part) comes off with 6 smaller clips; do not use excessive force – just enough to get around the male end.

The short-side clip comes off by pulling the top OUT, and then sliding it DOWN. The wire loom will get in the way a little bit so be careful and do not use excessive force!

The long-side clip comes off by pushing the screwdriver into the center, and pulling UP on the clip. Then you can remove the connector that plugs into the fuse box to give you more room to work with.

7) Cut the correct wire. The wire that comes FROM the Green 40A “ABS” Fuse is a single 14 gauge, solid black wire with silver printing of “AVS-3” on the side of it. This is the wire you want to cut. It is helpful to slide a paper clip down through the slots in the fuse box tray to help determine where this wire comes from.
Looking at the bottom side, you will see 2 wires coming out of the Green 40A “ABS” Fuse: 1) the black wire previous mentioned. This will come shooting out perpendicular to the tray. 2) A much thicker wire that feeds 2 other fuses via a metal strip embedded into the tray. Leave that one alone!

Briefly, to give you some education on what you’re about to do, here are a couple simple wiring diagrams:

Pictures for Step 7:

NOTE: “AVS-3” in silver print!

Government Approved
363 Posts
Discussion Starter · #2 ·
8) Solder on wire extensions. After making your incision, measure out roughly how much wire you will need. I did not measure myself, but longer is better! My estimation is between 6 and 7 feet, and you’ll need 2 of them. Here are a couple good sites on how to solder and use heat shrink:
My additional insight is to also “tin” the wire ends before soldering. This is essentially heating up the wire end and adding solder onto it so that the solder melts into the wire. Do this before you combine the two wire ends together. These are thicker wires and do not twist easily, so if you have solder on the wires before you combine them, makes your life easier.

Heat shrink and apply electrical tape as needed to cover exposed wires.


At this point I stripped the end of this wire to mark it “ON”, and left the other wire fully insulated.

It may help to tape the ends of the wires together for the next part.

9) Running the wires. Follow the largest diameter wire loom to the firewall (rear of engine bay). Here it passes through a nicely sealed rubber grommet and into the interior above the clutch pedal (or in that general area for auto’s). The best way to look at it is by moving the driver’s seat back, laying on your side/back and easing your head into where the pedals are. This seal is inserted from this end believe it or not, and will come out by pulling on it… from this end. We only need to pass 2 wires through, so we only need to peel back one side of this circular grommet, since passing it through the middle where the other wires goes, may be more difficult… (if you can do it, go for it!, but you may risk damaging the seal. This is an area of improvement – maybe there’s a connector that I missed that will allow us to slide the big wire loom in and out of the grommet.)…Then push the grommet back into place once the wires are through.

To avoid using excessive amounts of zip ties in areas that don’t accommodate our hands very well, we’ll use some of the holes in the structural components of the dashboard, to ‘snake’ the wires through. The other idea here is to keep these wires clear of your feet when driving! Using my carefully calibrated eye for rough dimensions here: I ran the wires from the grommet through a brace with a 0.75” hole and then down through the 0.25” hole as seen here:

Then I ran them across the bottom of the steering column trim piece to another 0.25” hole, near the center console.

(looking towards the center console)

10) Remove the radio bezel and cubby compartment. Remove the air conditioning knobs by simply pulling them off, revealing 2 screws to be removed as well. The entire bezel just simple pulls off. I recommend using the air vents as handles, and working your way down, carefully prying the bezel off (it’s only clipped in). The cubby compartment is also only clipped in on the sides.

11) Mounting the switch. You can choose anywhere you want really, but I chose the blank panel above the cigarette lighter/ 12v outlet. Once the cubby compartment is removed, you can pop out these blank panels so you can trim them away to mount the switch. I didn’t take pictures of this, since switches come in all shapes and sizes, but basically make a small hole, and work your way larger and larger until you get a nice snug fit! My ON/OFF switch ($7.00 from a local hardware store) had little clips on the sides to keep it in place.

12) Run the wires to the switch. From step 9, run the wires into the center console area (you’ll be able to see daylight from the pedal are now) and to whichever opening you chose. I taped the 2 wires to the cigarette lighter wire loom just to keep things tidy. Once the wires have made it through the hole (with the bezel removed still), cut the excess wire so that only a few inches remain… one at a time so you remember which one is which!

Strip the ends of the wires that remain – only about 0.25” of exposed wire is needed. Using the female connectors, crimp them onto the ends of the wires. There are special tools, but a small vice or pair of pliars will work as well. Again, mark the wire that is in the ON position – I used a sharpy marker this time.!/step3/Crimp/

Needless to say, once the two wire ends have connectors on it, and the switch is mounted, plug the connectors onto the correct prongs and re-install the panel and radio bezel.

13) Fuse box reassembly. Check to see if your wire connections are ok (which they should if your soldering was done correctly! Bundle up the wires and place them roughly along the main loom. Carefully bend the fuse wire 180 degrees, before the solder joint, so you bend the wire and not the solder.

14) Reassemble the car. Assembly is reverse of install :)

From my previous testing, I believe that once the aids are turned back “on” with the switch, they will turn back on, but the 4 lights will still remain lit on the dashboard until you turn the car off. I will verify this once the snow falls (hopefully a moderator can edit this when that happens!).

Thanks! Comments and criticism are always welcome

06.5 TCM
10,027 Posts
Good job showing the process:cool:
Getting to the back of the fuse box seems to be the bigger part of the project.
How about removing the ABS fuse, plugging wires instead and running them through the firewall to the switch. And just use remote JCASE fuse holder. Not gonna be as hidden as tapping into the wires underneath, but a little less involving.


Government Approved
363 Posts
Discussion Starter · #4 ·
Yes, unclipping the underside is a big step, but not terrible though... hopefully I explained how to do that well enough!

Yes, you can certainly do that as well! I have seen/read other write ups for different vehicles where they do just that, but then decided that I didn't really like that idea, so I decided to dive in a little deeper.

Government Approved
363 Posts
Discussion Starter · #5 ·
Ok so revisiting this for a correction to my NOTE at the bottom:

The traction control does NOT turn back on when you flip the switch from off to on, when the car is on. You need to turn the car off in order for the driving aid systems to work again, which will also cause the lights to turn off. So in summary, the lights are correct when they are on.

Government Approved
363 Posts
Discussion Starter · #6 ·
So after playing around with this switch more this winter, I am making a change to the switch type... if anyone is following this.

Instead of the rocker SPST switch like I installed, a Momentary SPST switch would be more suitable. This type of switch only requires you to push a button and it will do the same thing, without rocking the switch back and forth.
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