Kill switch system? Your thoughts?

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Joined
Jul 25, 2023
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My Car
Ford Mustang 1972
I found this on amazon.com and thinking of getting it,
https://www.amazon.com/Knoweasy-Bat...16-98e3-62dd6a771724&pd_rd_i=B0CC5NCPFC&psc=1

Any one try it? Any issues? Any other suggestions?

My personal reservation, will it damage the battery I have in any way? Does it shut off when you drive all of a sudden? Also what's stopping someone to just put the old connectors back on the battery and remove this gadget?
 
If your intent is to make the car harder to steal, there are ways to slow the thieves down that don't cost much and are not obvious. Insert a hidden switch in the control lead to the starter relay, so the starter won't turn. Insert a hidden switch in the hot lead to the ignition, so the engine won't fire. Remove the high tension lead from the coil to the distributor and replace it with a fake, so the engine won't fire. Install a fuel cutoff valve, so the engine will only run for as long as it takes to use up the fuel in the carb bowl and fuel lines; they might get halfway down your street, but no further. Thieves looking to pop the ignition lock and drive the car away depend on being able to make a quick getaway. They don't have time to troubleshoot why a car won't run, and they probably don't know how. Of course, nothing will stop thieves who have a tow truck or trailer.
 
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One common method is adding a switch that lets you ground out your coil. I'm sure there are come caveats with that, and it may not work with all the different types of aftermarket ignitions and coils. So check with your specific type to make sure you wont damage it.

I have a carbcheater system. They have an anti-theft as well as a rev limiter. Both work by grounding the coil. You can use your phone over bluetooth to enable/disable the aint-theft. But if you dont want to go that advanced, a simple hidden switch and a wire will do the same.

A thief can try to crank your car. Make a bunch of noise and eventually kill the battery. But if the coil is grounded, it wont fire.

The disconnect OP linked to kills the link to the battery. Your radio presets are deleted and your clock is reset. Plus it looks like some cheap made-in-china stuff with zero support after the sale. But if you have a manual transmission,it doesnt actually keep somebody from pushing the car and dumping the clutch to get it running.
 
I try to use the KISS rule whenever possible.
When I had an MSD-6AL I grounded the unused Crank Sensor (white) wire through a hidden switch. That shut down the ignition. It was nice because hot wiring the coil made no difference.
With my Duraspark II system I use one of my P001 ignition relays and put the selector switch in the center (off) position. No more power to the coil.
 
If you run a fuel pump (low pressure carb or EFI). One of the safe things to do is to install an inertia switch and while it may sound strange on this thread, the little guy can be used like kill switch for the fuel.
A hidden line lock could do the same, making it even harder to load the car on a trailer. They also do help for burnouts! :)
 
I agree with others. Too much risk for an electronic device of unknown quality to control the entire electrical system. There are other mechanical methods of doing it, cheaper and more reliably. And, you are correct, if your hood doesn't have a lock on it just a couple of minutes is all it would take to defeat it.
 
I had a customer at our Ford dealership back in the late 70s who wanted me to rig a kill switch, using all current equipment in his new 79 Bronco. I asked if he smoked, or any of his family or friends, Nope, Okay then, I just ran a wire from the Negative Terminal for the Primary Ignition System through the firewall and over to the cigareet lighter. I removed the cigarette lighter power circuit, and connected the circuit coming from the Ignition Coil. When the lighter element was pressed in the Primary Ignition circuit was grounded - no start, no run. He loved it. I wonder if her told the next owner about that feature. heh heh... Quick, dirty, simple...
 
I have thought a switch in the negative of the coil and dizzy is easy way to go and just hide a switch in the car somewhere but I like mrgmhale’s idea of the cigarette lighter. No one would ever think that would be linked to the ignition system.
 
I had a customer at our Ford dealership back in the late 70s who wanted me to rig a kill switch, using all current equipment in his new 79 Bronco. I asked if he smoked, or any of his family or friends, Nope, Okay then, I just ran a wire from the Negative Terminal for the Primary Ignition System through the firewall and over to the cigareet lighter. I removed the cigarette lighter power circuit, and connected the circuit coming from the Ignition Coil. When the lighter element was pressed in the Primary Ignition circuit was grounded - no start, no run. He loved it. I wonder if her told the next owner about that feature. heh heh... Quick, dirty, simple...
That's brilliant
 
Using a vacuum hose as dummy coil wire and a removable post battery switch will usually slow the wannabe thief down.
Back in high school we (the guys in auto shop) would sneak out and replace a buddy's coil wire with a piece of like booted vacuum hose. It got to the point we all carried our coil wires in our pockets during school.
 
I plan on adding an electronic fuel pump and when I do I will wire a kill switch. I did this with my Jeep, which is also carbureted. Like my Jeep I will add a second key switch, probably hidden in the ashtray or in the center console, and a small speaker that sounds when the fuel pump is turned off. This keeps me from forgetting to turn it back on and having it die at very inopportune moments.

The plus about this system is the car (Jeep in my other case) will start and move but not far. The thief will be stuck in a parking lot lane or on the street with a car that just won't start and no time to troubleshoot the issue.
 
How do you charge your phone then?? :D
Back then, in the late 70s, we did not have that issue <g>... For current times I would suggest using USB outlets to charge a phone, as opposed to 12 volt outlets, but then comes the concern for where to mount the USB outlets. For me, it was easy. For both of our 73Mustangs the originalbuild used the small bezel that coveres the area near the shifter. I decided I wanted full length consoles, just because I like hows they look, and the added storage space was of interest. What I did was remove the guts of the ash tray (I do not smoke, so that was an easy place to work at), then I fabricated a Power Plate using a marine switch plate (from Amazon) along with a pair of 12 volt outlets, a dual UAS outlet, and an LED voltmeter display (all from Amazon also). I powered the outlets with switched voltage I tapped into the fuse block for, as opposed to having an "always hot" circuit feeding those sockets (and LED display). Doing that I could definitely use the oem cigarette lighter as a ground for the primary ignition negative circuit, and have plenty of outlets for phones or other devices from the Power Panel.

Following is a link tto my YouTube channel where I have a video showing, amongst other things, what the Power Panel on the consoles for both 73 Mustangs looks like:

https://www.youtube.com/watch?v=xSxEBNDKp7o
 
Back in high school we (the guys in auto shop) would sneak out and replace a buddy's coil wire with a piece of like booted vacuum hose. It got to the point we all carried our coil wires in our pockets during school.
I was "in competition" with a really sharp, and fairly experienced fellow student at the school I learned auto repair from (Los Angeles Pierce College). He worked as a part time tech at a local Texaco station, and he was really good with his diagnostic approach. We were friends, although with what I am about to share you may well wonder how that could be... heh heh... We were in the same tune-up and engine diagnosis class, as well as some other classes. Sometimes we had live cars with real issues to work on. Other times we worked on shop mock-up engines on engine stands with the necessary wiring and plumbing to provide for electrical and coolant needs for when those engine were running.

Well, one day we had no live cars to work on, and the instructor had to leave for a little while. He told us to just work on the mock-up engines, introducing problems for other students in our group to diagnose, in a kind of an ad-hoc round robin manner. So, we all got to it, introducing various problems then moving onto the next engine to diagnose what was done to it as another group was left to figure out what we had done to our victim engine. My Texaco friend was in the group following me. I happened to have a can of spray graphite in my tool box for some reason. Making sure he was busy working on the engine I had previously already disabled electrically, I removed the black distributor cap and sprayed some graphite inside the cap, then put the cap back in place.

Well, he found the problem with the prior engine(s) pretty quickly, which did not surprise me in the least. One of the kids in my group had seen what I did, and he said, "I bet you never find what 's causing the problem with this one!" I would have preferred to not have anyone say anything, but the hook was set and it was game on. So, we got through our next diagnosis quickly enough, but my Texaco friend and his group were pulling out every trick in the book diagnostically, but they were bewildered. They tested the ignition coil and it has plenty of juice to create a spark. The spark plugs were all clean. There was fuel, they checked and even swapped the distributor rotor. Our instructor came back just as the class session was over. It was my last class for the, as well as for Mr Texaco. But he normaally went to work after this particular class. He was beginning to get frantic as his group disbanded due to the class being over for the day. "I know it has to be something simple," he said. I told him I had nowhere I had to be and would hang out to help if he would like. Nice guy that I was. About 15 minutes later he asked the instructor if he could use the phone to call his employer to tell him he was going to be running late. Man, I felt like such a heel. This guy was as committed as he was confounded (and good). Before he placed a call I told him I was certain he would never find the problem unless he just began to swap parts. At that it would be the last part he thought of. I showed him my can of spray graphite and pointed to the distributor cap. He looked perplexed. I took the cap off and ran my finger inside the cap and showed him the graphite residue on my finger. "Dang! I would have never thought anyone would do that!" We had a good laugh and he headed off to work. I figured some day I would pay handsomely for that dirty trick. No harm done, all in good fun, but I am still waiting for the shoe to drop.

I do wish I had kept in touch with him. He was one hell of a nice guy. And full of his own kind of tricks.
 
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Yes, they really were the “good old days”,
This is likely the biggest reason I enjoy our hobby so much. Any time I work on one of our vintage pony cars, tinker with on, or drive one I am 19 again - and have not a care in the world. Eventually things catch up with me, but I am still quite pleased with how well things are going for me, even at 69 years of age now. If nothing else I have Lynda (wife) in my life, and some really cool cars we both enjoy together - a lot.
 
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