View Full Version : Roadster Remote Controlled Kill Switch
Anyone out there ever install a remote control kill switch?
I see that there are 12 volt remote controlled relays out there with 500 to 1000ft ranges that you can control with a key fob. It seems to me like it would be simple to wire one of these remote relays to the ground wire of the fuel pump - similar to the way the inertia switch is wired.
What do you experts out there think?
Thank you.
Edit: Initial post edited - would like to focus on technical aspects of building a remote kill switch.
JohnK
07-07-2021, 09:23 AM
Couple of thoughts... first off, a car (no matter how much blood sweat and tears I've put into it) is just a thing. No way I'd put my life in danger fighting with a carjacker over a car. The simple answer is to carry excellent insurance in the event it's stolen. Secondly, please consider the liability associated with what you're considering. Say you kill the engine as the carjacker is driving away, and they subsequently end up losing control and crashing the car and possibly killing themselves or somebody else. Do you want that liability risk in order to avoid losing a possession? Not trying to be argumentative but please think through what you're considering.
Rdone585
07-07-2021, 10:02 AM
Hidden fuel pump cutoff switch works for a carb setup. They might start the car but won't make it very far when the gas in the carb is used up. It will be a slow stop not abrupt. And since everything safety related (steering and brakes) is manual no issues with vehicle control.
cob427sc
07-07-2021, 10:06 AM
I agree with JohnK. Also, I would guess only a really stupid person would car jack that vehicle as it would be so easy to spot, plus unless he is a mechanic or someone over the age of 40 he probably couldn't drive it anyway! As far as theft of the vehicle, my suspicion would be only by a pro, maybe with a flatbed wrecker. I think they still sell GPS systems you could install in your car and track it's where abouts. When I used to park in the city I had a removable steering whell. Figured it stopped 95% on anybody thinking about stealing the car.
Thanks everyone - all valid points.
I just edited the initial post to focus on the technical aspects of building a remote kill switch.
egchewy79
07-07-2021, 11:38 AM
Couple of thoughts... first off, a car (no matter how much blood sweat and tears I've put into it) is just a thing. No way I'd put my life in danger fighting with a carjacker over a car. The simple answer is to carry excellent insurance in the event it's stolen. Secondly, please consider the liability associated with what you're considering. Say you kill the engine as the carjacker is driving away, and they subsequently end up losing control and crashing the car and possibly killing themselves or somebody else. Do you want that liability risk in order to avoid losing a possession? Not trying to be argumentative but please think through what you're considering.
valid points, but he's talking about killing the fuel pump, which would basically be the same as running out of gas. the car would just sputter and slowly roll to a stop. I guess his power steering would cut out making it harder to control.
Bottom line is to get good comprehensive insurance and you should need to worry too much about it.
FWIW, I installed a kill switch wired to my relay ground that needs to be turned on for my fuel pump relay to work. It's under my dash so I am able to reach it in the event of an accident that doesn't trip my inertia switch but also doubles as a theft deterrent if they don't know to flip the switch prior to starting the car.
JohnK
07-07-2021, 11:44 AM
valid points, but he's talking about killing the fuel pump, which would basically be the same as running out of gas. the car would just sputter and slowly roll to a stop. I guess his power steering would cut out making it harder to control.
Fair enough. I didn't study his setup specifically; I was merely thinking about the impact of losing power steering, power brakes, etc. Even the unexpected loss of engine power (especially for someone who isn't used to driving one of these cars) could cause a loss of control in the right (wrong) situation such as aggressively driving a car you just carjacked.
FLPBFoot
07-07-2021, 02:23 PM
valid points, but he's talking about killing the fuel pump, which would basically be the same as running out of gas. the car would just sputter and slowly roll to a stop. I guess his power steering would cut out making it harder to control.
Bottom line is to get good comprehensive insurance and you should need to worry too much about it.
FWIW, I installed a kill switch wired to my relay ground that needs to be turned on for my fuel pump relay to work. It's under my dash so I am able to reach it in the event of an accident that doesn't trip my inertia switch but also doubles as a theft deterrent if they don't know to flip the switch prior to starting the car.
The same as egchewy I too put in a hidden fuel pump kill switch and also an ignition kill switch. Stops the 12 volts from going to the coil. They can crank it all day and with no spark....nothing.
GTBradley
07-07-2021, 02:31 PM
I don’t think there is any car manufactured that would cause one to crash because the engine is dead. Except for when people have turned the key and pulled it out of the ignition on any car with locking steering :eek: I’ve seen a Russian do essentially the same thing in a plane though. That’s gotta get real exciting real quick.
Thinking about trying this as a remote kill switch to shut off power to the fuel pump. It's rated at 30 amps. Anyone have experience with this set-up?
150742
I have the Holley Sniper EFI with the sniper controlling the fuel pump. Any concerns about placing the kill switch between the fuel pump relay and the fuel pump, and using the fuel pump power wire as the power source? This means the ignition switch must be on to power on and off the kill switch - that's okay as my primary objective is to kill the engine when it is already running.
150743
I could install a hidden bypass switch via a jumper wire for back-up starting in the event of kill switch relay failure.
150744
I welcome your feedback. Thank you.
RBachman
07-12-2021, 10:59 AM
'Did the same thing. It's simple, effective, inexpensive, easy to use, and within a quick reach. Although, I do think having a key fob to "lock" the car by killing the starter and fuel pump is kinda' neat. But the same thing can be accomplished with how you configure a keyless start system.
Rdone585
07-12-2021, 11:00 AM
The rated range is 328 feet. Specified ranges are typically in an open field environment with best case conditions. You may see far less in real practice. If you are inside a building and there are trees or other vehicles between then the range could be less than 1/2 of the rating.
Hoooper
07-12-2021, 12:00 PM
Whats the benefit of using it as a kill switch rather than setting it up to just disable when you leave the car? Mine is set up so you cant energize the engine computer, starter, or release the e-brake without the fob.
Whats the benefit of using it as a kill switch rather than setting it up to just disable when you leave the car? Mine is set up so you cant energize the engine computer, starter, or release the e-brake without the fob.
Just exploring options. In addition to a disable capability while parked, I wanted to see about a jack-thwarting capability wherein you surrender the car, flee the immediate threat, then disable the car. Shutting down the fuel pump seems to me like the simplest approach so far. Would love to hear other ideas though.
egchewy79
07-12-2021, 04:28 PM
you have a vivid imagination. If I'm getting car jacked, I'm walking away and calling the cops once I'm out imminent danger. Insurance exists for a reason. I'm not going to play the hero, remotely cutting off my fuel pump as the car jackers speed away.
but to answer your question, cutting off the fuel pump or the spark would be easy ways to stop the car quickly.
There was an article on thedrive.com the other day that showed doorbell cam footage of a car jacking that went wrong when the thieves realized they couldn't drive manual transmission, and ran off. I think it was an acura from the 90s.
RBachman
07-12-2021, 04:32 PM
Just exploring options. In addition to a disable capability while parked, I wanted to see about a jack-thwarting capability wherein you surrender the car, flee the immediate threat, then disable the car. Shutting down the fuel pump seems to me like the simplest approach so far. Would love to hear other ideas though.
If car jacking is that big of a concern, maybe move? haha. The simplest method is a toggle switch in series with the rollover switch. This will shut down the fuel pump. Mine is under the dash. Easy to hit, hard to see and there's another big benefit. If you ever have a fire or fuel leak, you're gonna want it. If you really want to go the gadget route, there are a number of car alarms you can configure to work with a smart phone. Many just disable the starter (a safety thing maybe?), but you can run that switch to the pump instead. However, consider that if you put money toward that, you'll have less to put toward things that'll be more advantageous (like beer or a weapon permit, or both...I know you're up North a bit, but they do seem to go together on occasion here in the South, LOL).
RBachman
07-12-2021, 04:48 PM
you have a vivid imagination. If I'm getting car jacked, I'm walking away and calling the cops once I'm out imminent danger. Insurance exists for a reason. I'm not going to play the hero, remotely cutting off my fuel pump as the car jackers speed away.
but to answer your question, cutting off the fuel pump or the spark would be easy ways to stop the car quickly.
There was an article on thedrive.com the other day that showed doorbell cam footage of a car jacking that went wrong when the thieves realized they couldn't drive manual transmission, and ran off. I think it was an acura from the 90s.
I agree. For a number of reasons. I joked about being an armed citizen, but unless there is no other way of escape, it's not worth what it does to you (or the legal bills) to shoot or kill someone even when they deserve it and you're right to do so. It's not worth getting beat up over either, much less shot, stabbed or killed. They likely can't drive it anyway and if even they can, they're gonna floor it to get away and likely wreck before they get past 100 yards. That's what insurance is for...to save you that aggravation.
rich grsc
07-12-2021, 04:58 PM
I think you're too paranoid to own a car, maybe Uber is for you? :rolleyes::p
Seriously, these are one of the least likely cars to get stolen. They are so unique and stand out so much, why would they try, and as said, can't drive a stick shift anyway.
you have a vivid imagination. If I'm getting car jacked, I'm walking away and calling the cops once I'm out imminent danger. Insurance exists for a reason. I'm not going to play the hero, remotely cutting off my fuel pump as the car jackers speed away.
but to answer your question, cutting off the fuel pump or the spark would be easy ways to stop the car quickly.
There was an article on thedrive.com the other day that showed doorbell cam footage of a car jacking that went wrong when the thieves realized they couldn't drive manual transmission, and ran off. I think it was an acura from the 90s.
Yes, the manual transmission is a deterrent itself. Vivid imagination? I just want options. I would hate to wish in hindsight that I had installed a jack-thwarting device.
Also, I think each one of us on this forum has an opinion of how one should react to a carjacking. With that in mind, hoping to keep the thread narrowly focused on the building of such a device. Thank you.
egchewy79
07-12-2021, 05:23 PM
No worries. good luck with the build.
How about a remote controlled ejector seat? (aka airbag under driver seat?);)
https://youtu.be/gtUNczOl_AA
#popcorned
I agree. For a number of reasons. I joked about being an armed citizen, but unless there is no other way of escape, it's not worth what it does to you (or the legal bills) to shoot or kill someone even when they deserve it and you're right to do so. It's not worth getting beat up over either, much less shot, stabbed or killed. They likely can't drive it anyway and if even they can, they're gonna floor it to get away and likely wreck before they get past 100 yards. That's what insurance is for...to save you that aggravation.
I think everyone is missing the part where I said flee, then remotely disable the car when I'm out of immediate threat of harm. I get it, I'd flee to drive another day, and I carry good insurance. But if possible, I'd like to recover the car quickly after the jacker gives up and leaves the area and the cops arrive.
I think you're too paranoid to own a car, maybe Uber is for you? :rolleyes::p
Seriously, these are one of the least likely cars to get stolen. They are so unique and stand out so much, why would they try, and as said, can't drive a stick shift anyway.
You may be right about being paranoid. I just know everyone else thinks that too. Shhh... what was that?
Lickity-Split
07-12-2021, 06:43 PM
I agree with RJD about looking into various ways of trying to get the car back right away. Sure, insurance is a good thing to have, but you can't drive a check this weekend. And, I wouldn't want to wait another year while building another kit, or taking who knows how long to find a "suitable" and complete FFR roadster replacement.
Good luck.
rich grsc
07-12-2021, 06:52 PM
You may be right about being paranoid. I just know everyone else thinks that too. Shhh... what was that?
Nothing, nothing at all. All is good;)