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Car security

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I understand that some car theives are fairly quick when it comes to bypassing the ignition key lock. I don't know if it's as simple as shorting two wires but it sounds like you'd like to reduce the likelihood that someone who is quick from getting your car started.

I have given this some thought myself. There have to be a dozen or more circuits in an auto, that when opened will result in non-operation of the engine. Certainly you can add a switch to the starter solenoid circuit to essentially disable the starter. With enough time someone would figure it out however it would take time - more or less time depending on how well you disguise your wires. There are any number of wires going to or from the ECM (computer) that would cause the engine to stop if broken. You could add a switch there. Interrupt the circuit in an electronically controlled transmission and it might go but not far.

I would expect that car thieves who are good enough to steal a car without a key practice or know some kind of bypass procedure. Some of this procedure has to be dependent on the wiring color codes. You might carefully swap some wires around but make sure you keep track of what you did.

Note that I tend to avoid modifying the wiring that is critical to vehicle operation. Along with voiding warranties it also can confuse a repair technician - not what you might want if you are depending on the technician for help.

This discussion brings to mind an old trick - simply pulling off the high voltage lead off the coil was enough at times.
 
philipsi said:
is that any way to prevent a car theft from shorting up two wires to start the car wihtout the key?

I wouldn't have thought you could do that on any vaguely recent car? - you certainly could on very old cars, you just needed a wire from the +ve of the battery to one side of the ignition coil - and that was it!. I've done it many times in the past, but only for completely honest reasons 8)

But anything at all recent is likely to have engine management systems (which make things far more difficult), and most likely an immobiliser as well. My Fiat Punto has an immobiliser built in the key, this seems a common way of doing it - so with the key you don't even know there's an immobiliser there, but without it the engine management system will be disabled (presumably?).
 
Yes, but when they see they can't steal it they'll get angry and smash up your car... So you lose, every time :cry:
 
ive thought about putting a transmitter in my car (when i get one) that is activated by someone touching the metal of the car. The transmitter would make a vibrator in my pocket go off.

For a switch, maybe you could put a switch under the car that you could hit w/ your foot or somewhere outside the vehicle that when pressed gives you enough time to get in the car and start it. If it isnt pressed, obviously the car wouldnt start. What thief would ever think to look outside the car for a switch?
 
Jumping some wires to start the vehicle won't get a thief to far, there are still steering and shift locks(if auto transmission) to overcome once the car is running.The simple hidden kill switch(ignition or fuel pump kill or both) will stop even the best of thieves.Sure if they want it bad enough, they will get it.But chances are they will just move on to another vehicle if you make it difficult enough(or time consuming enough) on them.
 
BTW I don't know about Europe or other parts of the world, but here in the US, the thief could file a lawsuit against you(and probably win) if you were to do something to deliberately hurt them while commiting the theft.

A few years back, I remember a story where someone put razor blades all over their stereo system inside their vehicle, A potential thief was badly hurt, and ended up winning restitution for medical bills.
 
Eclipsed said:
BTW I don't know about Europe or other parts of the world, but here in the US, the thief could file a lawsuit against you(and probably win) if you were to do something to deliberately hurt them while commiting the theft.

I can't comment on the rest of Europe, but in the UK defending yourself or your property is highly frowned upon!. Generally if you defend yourself against a mugger you would receive a far higher sentance than the mugger would - assuming the mugger ever actually got caught, he's likely to only receive a suspended sentence.

There was a case a couple of years ago where an elderly farmer shot a burglar with a shotgun - he'd already been burgled multiple times, and the police weren't doing anything about it (as usual) - the farmer was jailed, and the burglar was awarded free legel aid to sue for damages!. The UK polices response to most crime is to give you a crime number for your insurance company!.

As a martial arts instructor we teach not to involve the police!, if you're attacked defend yourself to the limit of your ability! - then leave, don't call the police, and make sure you leave no evidence, particularly DNA, and try and make sure there are no witnesses.

As far as I can gather, the official response should be to let the attacker kill you, then the police will make a vague effort to find the killer!.

As far as I'm concerned, I think it's better arguing in court than from a slab in the morgue!.
 
In Canada I believe anything purposely designed to injure is legally called a "man trap" and will get you into all kinds of trouble. It even goes so far as, if for example, you innocently left a ladder on a structure where children could climb and hurt themselves. This can be considered an "invitation to danger" and hold you liable for damages.

No wonder it has become more common for people to see the Golden Rule as : " do unto others, before they do unto you, then split"
 
I didn't read through all the posts, but you could try putting a kill switch to the battery in some discreat location, so even if they do try and hot wire the car there won't be an juice to get it going.
 
I know a guy who put razor blades inside the dash around the stereo after the previous ones were stolen. Lots of blood and no charges... be nasty if you were to have a heart attack or whatnot and keel over, then some poor soul (or your dad) starts parting out your car legally.

Now a stun gun, that's got potential.... thousands of volts of potential.

I would stick with less aggressive measures though. Removing the distributor HV line is possible, but not only is this a real pain, it's totally obvious to fix. Everybody I heard of doing this puts a switch in line with the fuel pump power. If you do not know where the switch is, you may not be able to find it or jump power around it.

The car may not start or may run for only a block until the carbs run dry. Leaving the car in the middle of the street sounds dangerous, but no thief is going to stick around to fix it. They've taken the car out of the safe hiding place of a garage or parking space, and after that, the cover's gone and it's time to run. Or if it doesn't start, they may assume the car was busted before they got there.

I think a fuel injected system won't start since there's little or no residual high pressure in the rails to power the injectors. Carbs have float bowls full of a small amount of fuel, but don't need it under pressure, so it will probably start.
 
personaly, I feel that is some little ****** ***** **** **** decides to break into your car, you should be able to anything you like with him/her.

However, in the UK, doing anything with your car that will stop it from working properly (which includes brakes that come on after you have started driving away) is illegal. Not saying its a bad idea, but it would be irresponsible not to point it out.

*sigh*
 
yes if you steal my beautiful car when i get it, i might decide to actually kill you. I'll do whatever i want with you even if it means breaking the law...

anyhoo, my simple approach is building my own transmitter/ reciever set and linking it up to a relay for ignition. If you don't like that, i would electrify the door handles of my car. I you dont like that or have clumsy children in your garage then get a gps tracking unit which doubles as onboard navigation

I reckon, if you choose to break the law, then the law shouldn't protect you from other criminals....that includes the original owner of the car btw. (i'm gonna give you a 2nd circumcision :twisted: if you steal my car)
 
put a fuel sut of on the car, so if it foes get started and the immobilizer aint switched off propely they fuel will be cut off, so the theif wont get far... u cud also use the brake idea the other way, as in the brake is permantly on
 
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