M35 Stagea Brake Cut Off Mod?

[Roachy94]

I worked through the wiring diags and found the brake wire, instant skids on a 3L DD v35.

I can confirm this first hand

[joshm35]

This mod would be well set up if it reset when you put car bsck into park.

[Daleo]

This mod would be well set up if it reset when you put car bsck into park.

Or onto the Handbrake switch.

[joshm35]

Either one is used in conjuction with each other. That way wouldnt need a switch so to speak

[joshm35]

I was just thinking if you used the dive circuit to complete the circuit once ot goes to either n, r, p it will reset due to tge circuit beind broken with these gear changes. With this in mind how is it with manual shift . Has anyone played with this. Are either drive or manual shift on samewiring circuit?

[joshm35]

Can someone quick link me to the drawing of the brake mod wiring diagram. I cant seem to locate it . If someone could point me in the right direction it would be great

[Commsman]

A quick point on the above questions, I had been thinking about the easiest/best way to achieve this.

One of my early thoughts was to use the ECU wire that sent the CEL signal. It would be sef healing - brake wire mod causes CEL, CEL output resets Brake wire input, CEL extinguishes. Win!

However, the CEL output is a 5V signal whereas the brake wire input requires 12V to reset.

So I had a quick scan thru convenient ECU pins & couldn't find anything suitable. Other switches are an earth on so also not suitable (not sure about all listed above).

In the end I connected mine to the reverse lights (already found for reverse camera) so reset every time I go into (or past) reverse gear.

I used the opportunity to install my 'Valet switch' at the same time, so needed a diode to stop reverse lights coming on when activated.

Josh, not sure if there's a diagram as such, but it's Pin 59 on the ECU if you have the pinout PDF.

[joshm35]

Cheers leon. Great more interior dismanteling

[Commsman]

For what's it's worth, I've knocked up a few pictures. These are very simple circuits, but sometimes a picture is worth more than a heap of text.

1. In it's simplest form. Switch required to clear CEL

2. Better because resets automatically. NB. Can use any temporary source of 12VDC.

3. Optional valet switch (anti-hoon) upgrade. Diode required so reverse lights don't come on when valet switch operated.

And lastly, the ECU diagram (again) for those who don't have it.

ECU_PINOUTS 13_12_10.PDF

Cheers, Leon.

[scotty nm35]

Josh, not sure if there's a diagram as such, but it's Pin 59 on the ECU if you have the pinout PDF.

Pin 55. Pink wire with a blue trace.

[Commsman]

Pin 55. Pink wire with a blue trace.

Thanks Scotty, I should have looked it up properly before posting those pics, lol. Hopefully the diagrams are still helpful to someone - just note my error & cut the right wire

[scotty nm35]

No worries Leon.

I know a lot of guys read this thread and have a crack at it themselves, make sure you are cutting the pink/blue wire on the ECU and not the TCU as the gearbox controller is in the passenger kick panel. You will need to remove the glove box to get to the ecu plug.

[joshm35]

Cheers guys.

[richzx]

Is the wire accessable at the brake pedal?

[Commsman]

No worries Leon.

I know a lot of guys read this thread and have a crack at it themselves, make sure you are cutting the pink/blue wire on the ECU and not the TCU as the gearbox controller is in the passenger kick panel. You will need to remove the glove box to get to the ecu plug.

You're right - even though the correct ECU pin number is probably written 2 or 3 times in this thread & many more times in others, someone is bound to get it wrong. As you've hinted, we've already seen an example of a car being sold with a switch that disabled a pink/blue wire on the TCU, lol.

Good thing is pin 59 is probably not populated in our ECU wiring, so that should cause a rethink if anyone blindly follows my drawings. But I'm still ashamed of my gaff

Is the wire accessable at the brake pedal?

Maybe Rich, but not sure it's that simple. One of the wires on the brake assembly emits 12V when pedal is pushed (we used this to cancel the cruise control) & I think this is used to light the brake lights (prob via a relay). But when Pin 55 is cut, the brake lights still work, so probably comes off a different control/relay. You can try it if you like - it'd be interesting to know - but since it's quite simple to find & work on at the ECU I'm not sure it's worth the effort.

[joshm35]

So is the wire to be cut completely or spliced into

[Commsman]

It has to be cut completely so the ECU doesn't "see" 12V when you put your foot on the brake.

As long as the ECU occasionally sees 12V (approx every 400km) it won't know any different. That is why you need to either a) wire via a switch to restore the connection (put foot on brake, CEL goes out, open switch again), or b) wire to alernative 12V source that comes on during normal driving but won't interfere with you making use of the mod, ie the reverse lights.

The only restriction if following b) above is - you can't launch with full throttle in reverse, lol. I think we can live without that

[scotty nm35]

Pin 44 is the neutral switch input to the ecu, perhaps that is a good feed to splice in to...

[Jetwreck]

You will need the exhaust done, it is extremely restrictive, especially the dump/cat pos. That will help spool the turbo.

Speaking of which, I may be trying out an anti-lag button for mine to help spool the turbo at stall. I will let you know how it goes. (This should work with the emanage too.)

O really!

[Commsman]

Pin 44 is the neutral switch input to the ecu, perhaps that is a good feed to splice in to...

That could work, but I can't find any info as to what that signal is & CBB checking it myself.

The voltages from the switch to the TCM won't work (looked at those before).

Edited May 6, 2013 by Commsman