Phunk, if you still want to keep your brake lights functional, you might try doing this instead.

If you unplug the VDC harness behind your ABS junction box near your brake resevior, you can brake boost. If you plan to wire up a switch, I would do it here, and just kill power to that module with the switch. This way, you can break boost, and still keep your break lights functional for the street. Your speedo is killed, but who cares.

And damn...break boosting from a roll is really really fun!

 

OK guys, this topic seems a little too noob for people for who have post counts in the thousands. (just playing!)

Get your head under the dash...Look under the fulcrum point for the brake pedal...You'll see a little switch that is activated when you press the brake...You need to tap in to the wire (the one that goes to the ECU). Install a switch. Boom bang done.

The TCS lights do not come on for me...

 

We all get a lil newb sometimes!

bBrake boosting is such a great advantage when street racing and is damn fun as well.

 

Interesting

 

But driving around on the street without brake lights is kind dangerous...and cops frown up that...LOL.

But either method will work.

 

Sharif, the method I said about just disabling that single pin at the ECU would not turn off the brake lights. Its the cleanest method as in it eliminates only one single thing, and thats the stoplamp signal to the ECU... therefore everything is still functional 100% except the gas will not close under braking now.

But I am glad to hear it works out for you the way you did it, part of me just wanted to hear that when someone disabled the system they have been able to do it. Just motivates me to actually go do it now.

 

Can you post pics of this and where its at, I'm intersted in trying this myself. Now I know why I couldn't brake boost on the street. When I tried it NA I just thought it wasn't enough power. Now I'm FI and still couldn't so I figured it was something like this.

 

well do it and quit talking about it, and let us know how it goes, since youre off from work.

 

the jerk store called....

 

of course you couldn't brake boost when you were N/A .. you can't build boost with no form of Forced Induction to begin with.

 

LOL! youre still at the computer? get to work!

 

Ah....so it just eliminates the stop lamp signal TO the ECU. Very clever.

 

Brake boosting ftw. It's sooo much fun on the highway

 

Per the service manual that pin (101) is supposed to go down to 0V at the ECU when the brake pedal is released. You *may* want to tie the ECU side of that signal to a ground (chassis) to make sure it doesn't "float". (If you get a CEL - it'd be a remedy).

It'd be great if the VDC switch could be used to disable both at the same time - anyone know where in the service manual is the wiring for the VDC switch (is it on/off vs. momentary push)?

EDIT: I found it in the BRC.pdf section of the manual (for a 2004 G35 coupe) - looks like it'd be pretty straightforward with one relay from the VDC off switch (connector M9) triggering a relay that connects the ECU pin 101 to either the sensor or ground.

 

Any updates on this? I'm very interested in hearing your suggestions.

I played around with it tonight and no luck.

 

no updates from here, havent felt like climbing around the mess of FCON wiring in my car.

However, if you were to put a toggle switch on pin 101 of your ECU, i will almost guarentee you that you will be able to brake boost no problem when you open the circuit

 

I might have to try that one of these weekends (after the holiday). I was hoping someone else would have feedback soon and I wouldn't have to play guinea pig on it. Also, I'm running out of places to hide all these gauges and switches.

 

Sorry guys,
I understand what is being discussed but a little lost with the term 'Brake Boosting'. Could someone explain why this term is used?

 

I haven't heard that term either, but I'm pretty sure it is the technique of spooling the turbo up while cruising. then, you can let off the brake and instantly be at full boost. You are just creating a load for the engine/turbos to work against to get the turbos spooling.

 

Dammit...ok..I will try it. It's a lot easier than popping my hood, and fiddling around my engine bay. People will think I am reconnecting my NOS......sweet!