KILL SWITCH, AGAIN

#111

Looking at it again, I guess his sticker locations could be a little better. The ones on the outside are backwards.

#112

There’s a number of stories out there of corner workers and tech inspectors activating fire suppression when they meant to just kill the car. The 90% solution is to take positive control of the kill switch test during annual tech.

#113

I hope to never be in a position where a corner worker has to pull either, but if I am, I can’t help it if the corner worker can’t read FIRE or has never seen a kill switch. I didn’t think about the fact the decals are opposite on the outside. The huge E decal wouldn’t fit on the door pillar so I put it under the kill switch decal on the door. I still have another larger E decal, so I might put that on anyways incase the door gets knocked off.

#114

I definitely plan to do this. I also don’t plan to use the kill switch other than at annual tech with all the stories of them failing or causing issues.

#115

[quote=“rrroadster” post=49142]All right! Now the Kill Switch kills!

Thanks guys! [/quote]

I’m going to be wiring mine right near the terminal block and was hoping to eliminate the terminal block since it seems pointless to me to have a six inch wire from the kill switch to the terminal block instead of just eliminating the terminal block altogether.

I just wanted to run the connections by you guys first before I start hacking things up. I’m going to disconnect the big wire at the terminal block (one big wire in and three wires out (1 big, two small)) and connect them to the big lugs on the kill switch. The two smaller wires at the terminal block (DME power?) are wired into the spade connectors such that the alternator -> DME works normally but when the switch is opened/shut off, the engine side goes through the switch, to the resistor, and then grounds to the shock tower.

Does this make sense?

#116

[quote=“MrDomino” post=66216]
I’m going to be wiring mine right near the terminal block and was hoping to eliminate the terminal block since it seems pointless to me to have a six inch wire from the kill switch to the terminal block instead of just eliminating the terminal block altogether.

I just wanted to run the connections by you guys first before I start hacking things up. I’m going to disconnect the big wire at the terminal block (one big wire in and three wires out (1 big, two small)) and connect them to the big lugs on the kill switch. The two smaller wires at the terminal block (DME power?) are wired into the spade connectors such that the alternator -> DME works normally but when the switch is opened/shut off, the engine side goes through the switch, to the resistor, and then grounds to the shock tower.

Does this make sense?[/quote]
Nope. Gotta draw a diagram.

You lost me when you said “alternator -> DME” and next you talked about engine side and ground.

I don’t know that I’d bother with the resister nor the ground. Almost no one does that, to include (I think) the OEM design.

Obviously there’s two lines coming from the battery. As long as your kill switch cuts both lines and there’s no route directly from alternator to DME, it’ll work.

Re. your signature. Don’t be sorry. Your struggles for social acceptance, for the slightest gesture of affection from the opposite sex were not in vain.

Hmm. Ok, well maybe they were. That is sad indeed.

#117

It is more work, but seriously consider mounting the kill switch inside the protection of the cage. When I had my wreck a cowl mouthed kill switch would have been inaccessible, if not destroyed.

#118

[quote=“Ranger” post=66217]

Re. your signature. Don’t be sorry. Your struggles for social acceptance, for the slightest gesture of affection from the opposite sex were not in vain.

Hmm. Ok, well maybe they were. That is sad indeed.[/quote]

Haha. Engineering isn’t a major. It’s a lifestyle.

Also, I think I’m going to eventually mount the kill switch inside the passenger window in the vent there.

#119

[quote=“MrDomino” post=66339][quote=“Ranger” post=66217]

Re. your signature. Don’t be sorry. Your struggles for social acceptance, for the slightest gesture of affection from the opposite sex were not in vain.

Hmm. Ok, well maybe they were. That is sad indeed.[/quote]

Haha. Engineering isn’t a major. It’s a lifestyle.
[/quote]
Haha. Only if you choose for it to be.

Calculus, physics and celibacy. And we wonder why there’s no white kids doing it.

#120

The benefit of going back to school for engineering at 27 is that all those girls who are majoring in engineer are hot unlike they were 9 years ago.

#121

Slapstick is considered a lower tier of humor. I would encourage you to leave behind crude jokes such as lighting farts and explore instead the more subtle genres of wit. Find the wry in life.

Hot engineering chicks. Uh huh. Can’t hardly swing a dead cat w/o hitting a hot engineering chick. “Hey babe, why don’t you come over to my pad tonight? We can pull an all-nighter working on heat transfer.”

#122

[quote=“Ranger” post=66347][quote=“turbo329is” post=66345]
Slapstick is considered a lower tier of humor. I would encourage you to leave behind crude jokes such as lighting farts and explore instead the more subtle genres of wit.[/quote]

“I work for Mel Brooks”

#123

At least that’s what I think Slim Pickens says when he punches out a guard to get on the set of a musical. It’s been a while since I saw Blazing Saddles.

#124

Lol, ya, that’s the line. I should rent the movie for our kids. It’s so important to expose children to the classics, don’t you think?

“No, don’t shoot him, it will only make him mad.”

#125

Quick noobie question for those folks with their kill switch location on the passenger side at the harness bar/main hoop junction. This thread has been a great help. I’m wiring the Pegasus 4430 Master Battery Switch with Alternator Protection which is basically the same as the Bimmerworld switch. For those using the resistor, where are you connecting the ground wire to the car body and what gauge wire are you using from resistor to ground?

#126

Another thread revival. :slight_smile:

So a friend and I (he’s finishing up his SE30 car) decided to go the solenoid route for a master switch. Trying to finalize the wiring.

Cutting the main 2/0ga battery cable is a no-brainer. But, this thread seems to insist that the 2 wires running from the positive terminal of the battery have to be disconnected from the battery and each other. This makes sense since the small wire can supply power from the alternator to the DME.

My friend, however, went a different way. Not sure if he found this online, or came to this conclusion based on the troubles he was having trying to cut the OBC out of the wiring harness, but instead of cutting the power to the DME from the alternator, he instead cut the green power running to the DME from the OBC relay box.

It seems to have the intended effect – shutting off the car. Also, it’s a smaller wire that doesn’t need a beefy switch (though it is further away from the rest of the action). I’m planning on running a few remote cutoff switches in the car – one aircraft switch near the driver’s A-piller (probably coming out of the vent, next to a fire pull), one on the center dash next to the other switches, and one large push button switch on the main hoop by the passenger window. I’m considering following his lead.

Just wondering if there’s any fault in the “kill” logic here. It’s hard to determine from the ETM what the green wire does for the ECU. It just says it goes to pin 27. The black wire off the battery junction goes to, effectively, 3 pins marked as “power inputs”. But if cutting power to pin 27 shuts down the ECU and kills the motor, isn’t that sufficient? Any situation where this would fail to kill the engine?

Oh, and here’s a schematic I drew–I mean–uh… conveyed to a 4 year old… who drew it on a computer.

(for me, the GN wire would go to the ignition/run switch, but it would go to the OBC relay in an unmolested car)

Thanks,

Som

#127

Funny story - I just completed something very similar to what you’ve described here.

Pin 27 provides a 12v run signal to the ECU. When you cut that, the ECU essentially thinks you’ve turned off the key.

I wrote a blog post about this with a diagram which hopefully I can provide in a day or so. Here are some pictures of it installed.

#128

Som, it should work. The only drawback I can see is there will still be some current output from the alternator looking for somewhere to go while it winds down. The design of the Bimmerworld-type switches (with alternator protection as mentioned in this thread) will shunt that wind-down current to a resistor. In your setup, the power to the ECU will be cut and the engine will die, but the wind-down alternator current is still momentarily flowing into the rest of your wiring. I don’t think that would cause any problems though.

#129

Cool… think that’s what I’m going to do and just ignore the shunt resistor.

Was trying to think of a way to add a relay to do engage a shunt resistor, but then I thought the time to close the relay would probably be long enough to prevent the desired protection of the shunt resistor.

(plus, adding a relay to this whole deal takes it into the realm of “over complicated” compared to the other, more common approaches)

Som

#130

I like this setup for the simplicity, but I’m concerned about a power spike from the alternator killing something. If I did this setup where would I add the shunt resistor?

I’ve been researching and trying to wrap my head around this whole kill switch thing…