Clutch switch bypass switch

[Inodoro Pereyra]

Nooooooowwww I got you!
You want to use the neutral switch as a bypass for the bypass...

Let me tinker with it a little...

[Inodoro Pereyra]

Ok, one question: when you're NOT pressing on the clutch pedal, is the clutch switch open or closed?

[Ryan]

It says in 1st post. when clutch is engaged (pedal up) it is open.

[Inodoro Pereyra]

Sorry, I didn't see it...

Anyways, the way I see it, it's gonna be very difficult to hang a relay where the neutral switch is. The pin where the switch is connected to the ECU is a digital input, so it doesn't have the current capacity to feed the relay coil.
Your best bet would be to use a dual pole relay, and feed the coil off the neutral switch (disconnected from the ECU), and use one of the poles of the relay as the neutral switch for the ECU, and the other one for the bypass.
Now, doing it that way you will have the relay activating every time you pass neutral. Let me see if there's a simple way around that.

[Ryan]

This is what I came up with


but I think I have the circuit wrong. Otherwise, the car would start with clutch engaged and in neutral, which it does not.


Also, what problems may arise from using a non-designated ground? I mean... there are locations where 10(ish) wires ground themselves at a common point, often found when the 'ground' from a component runs back into the harness... I know there's one to be seen in the hatch, and a few in the bay...

[Inodoro Pereyra]

You didn't get the circuit wrong. Either the circuit in the wiring diagram is wrong, or we're reading it wrong.
The wire between both switches (where X-04 is) does not belong there. With that wire there, you're bypassing any one of the switches when the other is closed. That drove me crazy for a while...

Anyways, your circuit doesn't work. You're loading the ECU input with the relay coil (don't try it, you could fry the ECU), and at the same time your neutral switch is loosing the ground reference.

I came up with a circuit that should work. The bad news: the relay WILL click every time you pass neutral. No easy way around it.

Give me a moment and I'll post it.

[Ryan]

I was wondering how the ecm was sending signal to the neutral switch, and if it could handle an alteration to its circuit. Is it simple? as in, a constant applied voltage?

[Inodoro Pereyra]

Here you go.
Sorry it took me so long. Photobucket has been driving me crazy.



You need to disconnect the neutral switch from the ECU, and use it to drive the relay. The rest is pretty straightforward.

Let me know if there's something you don't understand.

[PoisonDrop]

I was wondering how the ecm was sending signal to the neutral switch, and if it could handle an alteration to its circuit. Is it simple? as in, a constant applied voltage?

The ECM does not send signal. It receives ground when the tranny is in neutral.

Anyways, your circuit doesn't work. You're loading the ECU input with the relay coil (don't try it, you could fry the ECU), and at the same time your neutral switch is loosing the ground reference.

You're looking at it the wrong way. The ECM input (from the neutral switch) is grounded through the neutral switch, not the other way around. Essentially, you're loading the neutral switch with the relay, not the ECM. And the neutral switch is mechanical, so you should be fine there.

You guys are reading way too much into this. Here's what you should do:

First off, put your tranny in neutral and test the ECM wire coming from the neutral switch for continuity to ground. Just to make sure. If you are concerned about the ECM, you can pull that pin while you're testing, but you should be fine.

On the relay, hook 85 to the neutral switch ECM wire, 86 to one side of your button, 87 to one side of the starter interlock switch (on the clutch pedal), and 30 to the other side of the starter interlock switch. Connect the other side of your button to a constant 12v source. This should get you exactly what you want.

Sorry I can't draw a picture, but I'm not really set up to scan and upload stuff from this computer. If you'd like, I could e-mail you a diagram...

I will also tell you that if you do what I described, it will NOT click every time you press the clutch.

[PoisonDrop]

Here you go.
Sorry it took me so long. Photobucket has been driving me crazy.



You need to disconnect the neutral switch from the ECU, and use it to drive the relay. The rest is pretty straightforward.

Let me know if there's something you don't understand.

OMG NO NO NO!!!!

You definitely DO NOT want to connect 12v to the neutral switch AT ALL. I have done this and it WILL start a fire. The other end of the neutral switch is connected to ground, and it WILL kill your neutral switch. I cannot stress this enough. That is how I lost my neutral switch.

[Inodoro Pereyra]

Here you go.
Sorry it took me so long. Photobucket has been driving me crazy.



You need to disconnect the neutral switch from the ECU, and use it to drive the relay. The rest is pretty straightforward.

Let me know if there's something you don't understand.

OMG NO NO NO!!!!

You definitely DO NOT want to connect 12v to the neutral switch AT ALL. I have done this and it WILL start a fire. The other end of the neutral switch is connected to ground, and it WILL kill your neutral switch. I cannot stress this enough. That is how I lost my neutral switch.

Poisondrop: you need to look at the diagram more carefully.
As I said, the neutral switch needs to be disconnected. OBVIOUSLY, it needs to be disconnected from BOTH, ground and the ECU.
If you look at the diagram, the neutral switch is connected BETWEEN +12V AND THE RELAY, not between +12v and ground.

[PoisonDrop]

What I'm trying to tell you is that the ECM does NOT provide 12v to the neutral switch. If you do what your diagram says, and hook up 12v to it you WILL kill your neutral switch. I have done this before and I still do not have a neutral switch.

[Ryan]

On the relay, hook 85 to the neutral switch ECM wire, 86 to one side of your button, 87 to one side of the starter interlock switch (on the clutch pedal), and 30 to the other side of the starter interlock switch. Connect the other side of your button to a constant 12v source. This should get you exactly what you want.

I will also tell you that if you do what I described, it will NOT click every time you press the clutch.

Does that not feed the neutral switch 12v?

12v through button through relay, through neutral switch, into ECM? and does 85 simply tap into, or cut into the ecm-neutral switch wire?

And to address the previous two posts... whats the difference if it goes from 12v - n switch - gnd or 12v - n switch - relay -gnd. Same shiz. too much current either way.

Plus, I can't safely remove the neutral switch from the ECM.

[PoisonDrop]

Even if you connect it on the ground side, that circuit does not make sense. It is over-complicated.

[PoisonDrop]

Does that not feed the neutral switch 12v?

The relay coil is the load that allows you to do this.