Learn me some launch control wiring
 

Yes, I know there are various threads discussing how to set up launch control, and yes, I've read through every one I could find. Somehow my pea brain can't seem to grasp the correct method for wiring it up, specifically with an on/off dash switch.

I'm running an MSPNP2 V2 on a 95' (neutral switch unplugged) if that has any relevance.

My original wiring was like so:
https://cimg9.ibsrv.net/gimg/www.mia...6ab5cfe902.png
This worked great and let me use LC, except that the switch had no effect on the circuit.


I then revised and came up with this new and not very improved design:
https://cimg4.ibsrv.net/gimg/www.mia...402d5cce08.png
As you can see, It just made it so LC never activated.

I believe I just have some fundamental misunderstanding about the ground or what signal the options port need to receive... What's my glaring issue?

Attachment 228017

Try this.

Update:

Went to try the suggested change, but didn't see how that could work since the options port needs an input. Turns out the issue was all on me... Somehow the pin connector for the clutch switch in the factory ECU plug had backed out and wasn't connecting with the pin. Hard to see because of the location of the plug but just had to push it back in and it works fine now.

Sorry for the confusion, but the "Always off" diagram was actually correct. Hopefully helps someone in the future.

Apologies, brainfart. I assume that the input expect ground when active. In your second diagram, the dash switch cuts the ground to the clutch switch when open. I would have it on the other "branch" if you want it to control the launch wire pin.

This is correct. Stock configuration uses the clutch switch in for launch. The launch in is only for using a different trigger and would require a internal jumper change.

The wire to launch in isn't doing a damn thing for you bud.

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