Permanent Traction Override Switch

[DarrenDriven]

WAIT! THERE IS AN EASIER WAY!

Link to @2superblus's alternative method:
http://www.ft86club.com/forums/showt...49#post1091849

AND ANOTHER WAY TO DO IT!

Link to @mig86's circuit:
http://www.ft86club.com/forums/showt...00#post1918300



...and now back to my original post...

Scion FR-S Permanent Traction System Disable Switch

Warning!
This DIY bypasses the three-second button press safety system that was placed on this vehicle to keep idiots from spinning their cars into trees, off of bridges and over small animals. Driving without traction control turned on by someone who doesn't have experience can be dangerous and might result in injury or death. I am pretty sure that Scion or Subaru aren't gonna pay your medical bills and I sure as hell am not going to, so don't drive with traction control turned off unless you are willing to face the consequences should something go wrong.

Purpose
Install a hidden toggle switch that, when activated, will cause the traction control system to automatically deactivate every time the car is started. The TRAC OFF button will still operate normally while driving the car so traction may be reactivated easily. With the hidden toggle turned off, the traction control system operates normally.

Method
A timed pulse relay is activated which completes the traction control button circuit for five seconds when the ignition is turned on. Because the timed pulse relay operates only on a negative trigger, a Bosch-style relay is used to convert the positive ignition trigger to a ground trigger. After the five second pulse the circuit is disconnected and the TRAC OFF button resumes normal operation.

Time required
1 hour

Tools needed
- 528T Timed Pulse Relay ($14)
- Bosch-style Relay ($5)
- Large flat-tipped screwdriver
- Small flat-tipped screwdriver
- Utility knife (sharp!)
- Wire strippers
- Crimpers
- Electrical tape
- Soldering Iron (and solder, duh!)
- 6' of thin wire (or 3' of doubled speaker wire)
- Flashlight
- Wire coat hanger
- Toggle switch of your choosing (Radio shack?)
- Connectors to attach wire to switch
- Connectors to attach switch to car
- Label material or white tape
- Black pen or marker to write on label

Here is a video showing the operation of the finished product.

[ame="http://www.youtube.com/watch?v=AyfmOJZ5toM"]Scion FR-S Permanent Traction Override Switch - YouTube[/ame]




And now, without further delay, here is the DIY...




1. Begin by removing the parking brake cover. You can just pull up on the side closest to the traction control switch and the entire boot assembly will pull straight up and pop off.





2. Move the parking brake cover assembly out of your way by rotating it.





3. Unscrew the shift knob and set it aside.





4. I used a large flat-tipped screwdriver to pop up the edge of the shift boot. There is a slot in which you can simply twist the screwdriver and the boot's plastic clips will release. You could probably also do this without the screwdriver by gripping through the boot and pulling up.





5. Unplug the traction control buttons. I like to do this with a small flat-tipped screwdriver. You can use the screwdriver to push the release button in while you gently twist to force the plug away from the socket. Completely remove the shift boot by pulling it up over the shift lever.

There are five wires in this plug:
Purple: +12V Positive for dash lighting
Black/White: Ground for dash lighting
Black/Yellow: Ground for Traction buttons
Pink: Signal wire for VSC button
Green: Signal wire for Traction button





6. Force open the plastic wire loom with your fingers and pry out the wire bundle. Use a sharp utility knife to CAREFULLY cut the plastic wrap and expose the five wires inside. Separate the black/yellow wire and the green wires from the others.





7. Use your wire strippers or utility knife to strip about 1/4" of insulation from the black/yellow (ground) and green (signal) wires. Be careful, as the green wire is very delicate. Don't worry about the exposed copper touching anything, there is no positive voltage running in these two wires.





8. Now get the extra wire that you supplied (I used small gauge speaker wire) and wrap it in black electrical tape so it will match the OEM wiring that is already in the center console. I wrapped about three feet of wire and it was enough.





9. Feed your wire from the passenger footwell into the explosed center console area.





10. Inside the console, run your wire along side the existing OEM black-taped wire harness (top arrow) and underneath the carpet (bottom arrow). I pushed my new wire into the existing white plastic clips so that any Toyota technicians that get nosy won't notice anything amiss.





11. Strip the ends of your two wires and form each end into a V with half the strands on one side and the other half on the other side. Slip your V over the exposed copper in the OEM harness. Don't worry about which color of your wires attaches to which of the existing wires as long as you get one wire onto each of the two in the OEM harness.





12. After slipping the V over the exposed copper, twist it tightly so it is firmly mechanically attached to the OEM wire. Then, solder the two wires permanently together right at the base of your V. Repeat this for the 2nd wire. You could alternatively use a 3M wire clip, but I don't trust them to stay tight over time. Plus, the green wire is SO thin that the wire clip method would most likely fail.





13. Tape each solder joint with electrical tape and then get all five wires back together. I added a red zip tie to tidy things up, but this only made it a little harder to stuff the wires back into the plastic loom.





14. Stuff the wires back into the loom and if you need it, add a quick length of electrical tape to prevent the wires from spilling out.





15. Back to the passenger footwell. Your wire should be waiting for you still.





16. Oops, lets go over the driver's footwell. I placed a flashlight on the passenger side and you can see there is a perfect place to pass your wire through just ahead of the center console.





17. Push your straightened and hooked coat hanger from the driver's side through the gap.





18. On the passenger side, slip your wire through the hook.





19. Pull the coat hanger through and your wire will follow. Here is the switch that I had laying around. It is ugly, but since it will be hidden (and has an easy-to-mount housing) I don't really care. Any toggle switch will work.





20. Here, I install the connectors so I can attach the wires to the switch.





21. Just in case a technician is under the dash, I want to label the switch so they will know what it is. I found some masking tape and wrote TRACTION OVERRIDE on it.





22. Here is my connected switch, labeled and ready to be installed under the dash.





23. Your switch will likely be different than mine, so I won't go into how I mounted it, but it is located just behind my OBD plug. I can easily reach it from the driver's seat and it won't accidentally get pushed by my foot.



THE END? NOPE!

[DarrenDriven]

So it turned out that the engineers were smart enough to program the ECU to recognize that the button is malfunctioning if it is held down continuously. The result was that the second time I started the car my traction button was locked out and I could not disable traction control. Turning the hidden toggle switch off, then restarting the car, fixed everything so there was no permanent damage caused, except to my ego. Damn you engineers!

I have solved this problem by using a DEI 528T Timed Pulse Relay that I bought on [ame="http://www.amazon.com/Pulse-Timer-with-Spdt-Relay/dp/B0009WP09K/"]Amazon[/ame] for $14:

The 528T relay was advertised as providing a variably-timed output up to 90 seconds from a positive or negative trigger. When installed I quickly realized that the positive trigger (ignition +12V) would not trigger the relay's pulse, so I was forced to convert the positive input to a negative input with a standard Bosch-style relay. I am not happy about this as it is a very inelegant solution, but for now it works just fine. (DEI's tech support would not help a non-DEI official distributor and basically told me to eff off) It seems that the 528T will trigger with a negative input, or a disappearing 12V input, but a +12V input does nothing. Grrrr.





24. Mount your 528T relay out of the way with some zip ties. Mine fit well up high under the steering wheel. It's really easy to pull the lower plastic knee guard out of the way to access this area.




25. Run the red, black/white and black wires over to the wiring bundle over the fusebox. In those bundles you will find and connect respectively to the green wire (constant +12V), the red/blue wire (ignition +12V) and the black/yellow wire (ground).




26. Now wire in your Bosch relay according to the wiring diagram that I have supplied below. This will convert your positive ignition +12V signal to a ground so that it will trigger the 528T pulse relay. As I stated before, the relay is advertised to operate from a positive signal, but mine would not so I had to wire in the relay as a fix. I also put some nice wire loom over my wires so they would blend in better.




27. My two output wires (yellow and brown) look better twisted together, so I put them into the end of my drill and squeezed the trigger slowly to clean up the install.




28. Lastly, I just cut one of the wires that I had running to my hidden toggle switch and connected my brown wire to one side and the yellow wire to the other. It doesn't matter which.





Here is the wiring diagram for our circuit:










Here is the instruction sheet that came with the 528T:








.

[Lil Abner]

Cool idea. Although, it makes me wonder if "holding" the button on while driving would cause any issues with the car.

Also, you might want to put large letters at the top that you're not responsible for people who install this, then crash into phone polls!

[xclusive_brett]

why can't you just hold the button for three seconds? Seems like a lot of work for something the takes three seconds to turn off

[DarrenDriven]

Abner, good idea. I placed the "fine print" in bold red letters at the top. I held the button down for ten minutes last time I droe the car to see if there were any ill effects and nothing happened. I don't think that having the button pressed "permanently" will cause any errors... but if it does they won't be permanent errors and it is easy enough to switch the bypass switch off or remove the added wires completely.

Brett, I probably wouldn't have done this if I could simply turn off traction control with a button press, but since I am used to driving RWD vehicles that don't have traction control it bugs me that I can't permanently disable it. So basically, I press the button for three seconds every time I start the car and THAT is annoying!

By the way, I could have probably done this in 15 minutes if I hadn't been taking photos the entire time... and less if I already had a DIY telling me exactly what to do! So to me the time is not wasted.

[xclusive_brett]

It would be nice if you could program it to stay off instead of using the button. I like your idea, but i'll just live with holding the button. Keep up all the work!

[DarrenDriven]

You know, in theory I could wire up a time delay relay that would close the circuit for five seconds and then open for the rest of the drive. That would turn off traction control but still allow for normal operation of the traction button after five seconds. Hmmm....

[Hawaiian]

Originally Posted by DarrenDriven

You know, in theory I could wire up a time delay relay that would close the circuit for five seconds and then open for the rest of the drive. That would turn off traction control but still allow for normal operation of the traction button after five seconds. Hmmm....

You could also put it where the snow mode button goes for easy reach if you have a manual.

[jimmillion]

Originally Posted by DarrenDriven

You know, in theory I could wire up a time delay relay that would close the circuit for five seconds and then open for the rest of the drive. That would turn off traction control but still allow for normal operation of the traction button after five seconds. Hmmm....

since the rockerpb closes the circuit and pulls the button to ground, what you want is a NC-Toff (Normally Closed - Time off) relay to open the circuit restoring operation to the button after five seconds.

I personally like the idea of a hard override that even disables the TRC button, that way you don't accidentally reengage it if you brush the button. So I would personally leave the relay out.

let us know what you decide on doing

[DarrenDriven]

Well, the switch that I wired in does in effect disable the traction control button since pressing the button would only ground the signal wire that is already grounded. I probably will not change the setup that I have, but if someone else locally wanted me to wire their car I might try the timed switch idea.

[DarrenDriven]

Originally Posted by Hawaiian

You could also put it where the snow mode button goes for easy reach if you have a manual.

I thought about that, but I wanted my switch to be hidden. You would need to add a switch to the snow mode blank that would match the look of the interior and that would be tough... especially since you need a mechanically-thrown switch that will stay latched -- that eliminates the possibility of using the snow mode button from the A/T.

[xcelir8brz]

subscribed

[russv]

This might be an issue with the insurance company in case of an accident. Just saying...

[DarrenDriven]

Originally Posted by JIMs|a|MILLION

since the rockerpb closes the circuit and pulls the button to ground, what you want is a NC-Toff (Normally Closed - Time off) relay to open the circuit restoring operation to the button after five seconds.

I personally like the idea of a hard override that even disables the TRC button, that way you don't accidentally reengage it if you brush the button. So I would personally leave the relay out.

let us know what you decide on doing

Well, I was wrong... the ECU is smarter than I am and has decided that the button is stuck and solved the problem by not allowing the traction to turn off. Luckily, turning my override switch off and cycling the ignition reverts everything back to normal so no big deal.

This means that I do need a time delay circuit. I tried to build one today using this diagram:
http://www.the12volt.com/relays/page5.asp#ctm

I upped the 1K capacitor to a 4.4k (the largest at Radio Hack), but I still only got about 1/2 second of output then I want five seconds. The capacitor was the size of a C battery!

Here is one for ~$30, but I think that I should be able to do this cheaper. Any electronic wizards that know how to wire something up that will provide a five second output when it receives a constant input?

http://www.wolstentech.com/products/...delayrelay.php