HOW TO: Wire a Hidden ignition kill switch

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great white

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Lord jeebus man! what's going on in your dash! wiring everywhere!

Just kiddin ya. Most guys look like that anyways. I'm just really picky about that kind of stuff.

Only problem I see with your switch is that it's in plain sight when you open the door. Someone who rips cars "semi-pro" is going to notice it. Of course, they know almost all the other spots that kill switches are hidden too.

There's two ways of hiding the kill switch that I like.

One is to use a reed switch. That's a fancy name for a magnetic switch. You hid it behind the dash plastic somewhere and when you swipe a magnet across it it connects. This triggers a dual relay circuit in the dash on your cut wires to connect. The relays latch and the truck runs. Then, when you shut it off the relay unlatches and the truck is dead until you turn power on again and swipe the magnet across the reed switch. You can activate the circuit with ACC power on/off or you can use a switch to break the power to the latching circuit.

The other way is to use something already in the truck. For example: amp turn on circuit. I have used the remote amp turn on to activate a relay that is the starter kill. You get in the truck, you turn on the radio and the starter circuit energizes. Then you can start the truck as normal. Turn the radio off with the truck and the next guy can't start it. Who thinks to turn the radio on to start the truck if they're trying to rip it off? Only thing with that is if you leave the radio on, the truck will start. But it gives you an idea how you can hide it.

I've also done a little bit more complex installations like a relay circuit with e timer circuit. If the switch isn't thrown by the time the timer runs out, the relay opens and the fuel pump dies. A thief/joyrider with a truck that stops in the middle of the street usually just abandons it because now he's in the spotlight.

You want to make them as uncomfortable as possible. A dead truck in the middle of the road is just not what they want to deal with. Too much attention all at once. A kill switch they will take a few extra moments to hunt for in the parking spot because it's a low risk scenario compared to dead in the middle of the road. A truck that they can start easily is also less likely to be torn apart in the attempt to steal it. But then it stalls out halfway down the road and they are highly likely to just abandon it rather than frig with it more....

:)
 
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superdave

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I just used to pull the ignition fuse in my daughter's cars when I expected they would be up to no good. It would turn over all day, but not start. I was always able to fix it.

It isn't a theft deterrent, but it works good with kids. Still never came clean on that one. I still have 2 to get through the process.
 

great white

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I just used to pull the ignition fuse in my daughter's cars when I expected they would be up to no good. It would turn over all day, but not start. I was always able to fix it.

It isn't a theft deterrent, but it works good with kids. Still never came clean on that one. I still have 2 to get through the process.

That's just a dad doin' his job......
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Still, fuse pull is simple but effective.

As long as there's no spare fuses.

:)
 

gmcyukondriver

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That's just a dad doin' his job......
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Still, fuse pull is simple but effective.

As long as there's no spare fuses.

:)

If his daughter is anything like the girls I know, she wouldn't even know what a fuse was. :lol:

I'm going to do a couple different kill switches in the future, probably coil and fuel pump. I just need to figure out if I want to try to hide them with OEM switches, or stick them somewhere that no one will find them.
 

superdave

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I would honestly think a factory fog light switch in the dash would be perfectly hidden.
 

great white

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I would honestly think a factory fog light switch in the dash would be perfectly hidden.

Agree.

As long as the truck actually has fog lights that is.

You would be surprised how much a thief actually notices.

Joyriders are a different story....
 

Ruger_556

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Why not just pull the injector fuse? Little less convenient but super easy :shrug:
 

meterman

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there use to be a relay that u would ground with power to it and it would stay closed till power was lost we called it a ghost switch would use a random screw in the dash <trim> you turn key on and hold metal like gear shift and touch bolt the ground would close relay , would not start unless u ground the trip . can not remember who made this been early 80s
thanks mac
 

98WhiteZ71

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Thinking about doing this on my truck. Just want to make sure is the Purple wire typically the same for all GMT400 for the ingnition?
 

Nathaniel2g

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Thinking about doing this on my truck. Just want to make sure is the Purple wire typically the same for all GMT400 for the ingnition?

Just find a wiring diagram for your truck and double check. I made the mistake of not double checking for the 4HI mod and ended up splicing into the wrong wire for my low beams (brown instead of tan).
 
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