Alarm/Kill Switch Ideas

While searching around for kill switch ideas and seeing some people posting about installing "dummy" or switches that need to be turned on/off in a certain order to make it difficult for potential thieves from starting their rigs. I came up with an idea for a kill switch system.

A "fake" kill switch in a somewhat visible/obvious that when turned on activates a loud alarm, bright flashing LEDs on the outside of the vehicle, and super bright LEDs positioned such that it would difficult for the "thief" to visually relocate the switch to turn everything off.

A second less obvious "fake" kill switch wired to the fuel pump that allows the vehicle to start but activates the outside flashing lights. That way if they try to shut the flashing lights off, the vehicle also turns off.

Lastly, a very well hidden kill switch that allows the vehicle to be started and operated normally.

Probably overkill, but hey. I'm not exactly sure how I would wire the flashing lights to 2 separate switches. What do y'all think?

I looked into this a while back, one idea i read about was someone who installed a hidden kill switch, and then a more obvious "ignition" switch that was actually hooked up to the horns.

Sounds like a good idea to me.

BTW, here are some other ideas:
- on 93ish and earlier vehicles you could put the switch in series with the fuel pump ballast resistor. It'll start and run for a couple seconds but then bog and stutter and die, and probably do so right in the middle of your road. This will likely spook the thief enough that they abandon it since they're now stuck in the middle of the road likely within eyeshot of the owners house and can't get it to run reliably. It'll mean the police respond to your stolen vehicle stuck in the middle of the road quicker, too.
- you could put the switch in the CPS signal wire instead of the fuel pump if you want to use a smaller switch and hide it. Fuel pumps are fused for 15 amps or so, but the CPS signal is tiny, only milliamps at most, so you can use essentially any size switch.
- you could use a reed switch hidden under a cupholder or inside the dash and a cleverly wired relay in self-latching configuration to only require that you pass a magnet over a certain spot in the dash to latch the killswitch off... until you turn off the ignition at which point it will need to be enabled with the magnet again. If you want to use this on a 12VDC circuit all it takes is one auto relay, two small diodes, and a reed switch, if you want to use it on a signal circuit like the CPS you have to use a DPST or DPDT relay instead of just an SPST or SPDT one.

Just use the cigarette lighter as a kill switch , you can use it to stop a relay from coming on . if you really want to make even harder you can take the lighter with you , people see cigarette missing all the time so one missing looks normal .

blaqueowl said:

While searching around for kill switch ideas and seeing some people posting about installing "dummy" or switches that need to be turned on/off in a certain order to make it difficult for potential thieves from starting their rigs. I came up with an idea for a kill switch system.

A "fake" kill switch in a somewhat visible/obvious that when turned on activates a loud alarm, bright flashing LEDs on the outside of the vehicle, and super bright LEDs positioned such that it would difficult for the "thief" to visually relocate the switch to turn everything off.

A second less obvious "fake" kill switch wired to the fuel pump that allows the vehicle to start but activates the outside flashing lights. That way if they try to shut the flashing lights off, the vehicle also turns off.

Lastly, a very well hidden kill switch that allows the vehicle to be started and operated normally.

Probably overkill, but hey. I'm not exactly sure how I would wire the flashing lights to 2 separate switches. What do y'all think?

Click to expand...

Yeah... that sounds like overkill. Who do you think is going to put so much effort into stealing your jeep and why? Just seems like just a lot of wiring and switches that are likely to fail and cause you problems down the road. I can see a kill switch if your in a high crime area or abandoning it for a long period; and maybe if your paranoid a fake one; but three is getting out there.

What is the purpose of the second switch? They can start the car and drive away but have to deal with flashing lights, I don't get it. What the advantage of that? Might as well just not let them drive away. At that point I think your better off wiring up a system where they have to toggle switches with a combo. But if it is coming to this level of paranoia you should assume the thief will probably try to hotwire your kill switch circuitry itself so...

To answer your specific question you could easily have two different switches toggle the lights by using a relay. If either switch is activated the lights will go on, a separate relay can turn on the fuel pump when only the switch(es) you want are activated.

or wire your "kill switch" to a timed shut-off. When the vehicle is powered up, the fuel pump stays on for, say, 30 seconds. Starts and dies. Starts and dies. Thief thinks there's something wrong with the vehicle rather then looking for a kill switch.

I use a little different method. I have a hidden fuel pump switch that runs through a slow-blow fuse.
It allows the engine to start and run for about 10 seconds, just long enough to get out of the driveway, before it quits.
Most thieves will not spend too much time trying to figure out what happened and will run.
Turning the kill switch to the 'run' position bypasses the fuse and allows the fuel pump to operate normally.

This method is useful for both the fuel pump or ignition circuits.
It saved my VW Baja Bug many years ago, I heard it start and by the time I got outside, it was stalled out in the street, by the neighbor's house, with both doors wide open. The thieves were long gone.

lazyxj said:

I use a little different method. I have a hidden fuel pump switch that runs through a slow-blow fuse.
It allows the engine to start and run for about 10 seconds, just long enough to get out of the driveway, before it quits.
Most thieves will not spend too much time trying to figure out what happened and will run.
Turning the kill switch to the 'run' position bypasses the fuse and allows the fuel pump to operate normally.

This method is useful for both the fuel pump or ignition circuits.
It saved my VW Baja Bug many years ago, I heard it start and by the time I got outside, it was stalled out in the street, by the neighbor's house, with both doors wide open. The thieves were long gone.

Click to expand...

That is pretty slick. How/where do you guys actually splice into the fuel pump circuit? Is there a way to do it in the cab? Or do you run a wire back to the fuel tank?

I have run a magnetic reed switch behind a plastic portion of the console. The switch is in series with the control signal to the fuel pump relay. Without the magnet, the fuel pump does not run.

To find the reed switch you would have to pull the console. You just remove the magnet when you do not want it to run.

If I'm parked in a sketchy neighborhood, or overnight motel stay, long term airport parking, etc.; I just pull the ASD relay. That pretty much shuts down the major components needed to make your XJ run.

If you want to make it a long term solution, just run a hidden switch to the ASD relay circuit so you don't have to pull the relay manually.