Kill switch wiring

[JoshS]

Quick and dirty method:
wire the alternator output to the battery side of the cutoff switch. no need to fiddle with field wires, ECUs, fuel pump relays, nothing.

when you flip the switch, there is ZERO power anywhere under the hood. Zip. Zilch. Nada.

Uhh ... except for that big wire going to the alternator ... Doesn't cut "all circuits."

[Flyinglizard]

That is the only way to do it with a 2 post switch. It is the common way, not the ideal way but it is done.

[Matt93SE]

Uhh ... except for that big wire going to the alternator ... Doesn't cut "all circuits."

since the field coils on the alternator are cut, it effectively cuts "all circuits". All sources of power are on one side of the switch, all users of power are on the other. You flip the switch and the car stops. right now. What else do you want?

[JoshS]

since the field coils on the alternator are cut, it effectively cuts "all circuits". All sources of power are on one side of the switch, all users of power are on the other. You flip the switch and the car stops. right now. What else do you want?

Maybe that's good enough, and as I think about it, maybe I'm colored by the fact that my car has its battery in the back. I was trying to avoid having any electricity in the engine compartment. But I suppose if the battery is in the engine compartment, that's not a realistic goal.

But it says "all circuits" and as long as there's a circuit from the battery to the alternator, to the engine ground, back to the battery, it's hard to argue that it meets the letter of the rule.

[Matt93SE]

My battery is in the trunk as well. the only wire that's hot going into the engine compartment is the short wire going to the alternator. If you're in a wreck big enough to rip the alternator off its mount or break the engine loose, then a little #8 cable is the least of your worries.
As for cutting all circuits, I would implore you to argue that one to tech. this method cuts anything and everything that uses power or could keep the engine running. there is ONE wire going into the engine bay that's still got juice on it, and it's not going anywhere that's going to keep the car running. That's the intent of the rule, is it not?