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Tech Reference Page #13

Thoughts on security

Authored by Wes Vann, last modified on February 22, 1999

What I am going to try to do here is give ideas on car security. The electrical background that I have gives me a little incite to things that can be done. It's just ideas and you will have to figure what you need for a little piece of mind.

There is one thing that you have to face. It's possible for any car to be stolen!! All you can do is make your car more difficult or time consuming than what thief wants to do. Keep the thief guessing and spending time!

A lot of the systems that are available can't be purchased over the counter and have to be installed by a "factory installation center". I personally think this is bogus, but if you find a system that fits your requirements (or you can't do the work your self), shop around for an installation center that does work up to the quality you expect.

Options and functions vary from company to company. When looking, be sure that you are clear on what the system will do and how it will work. In writing this, I am using a "Derringer 2" system from VSE as an example. It's what is in my car and I have used their products in the past. I'm not out to endorse any product, but I've been very happy with their technical support.

General comments and notes; (things to be said up front)

1. I feel that the fact that you have an alarm system should be notable to the thief. What the system entails, shouldn't be visible. That is the reason that I feel that a system should have a "chirp" when activated. If there is an indicator "led", it should flash.

2. I am not going to go into systems that have a hidden switch for alarm activation due there being just too many possible variations. One quick comment though, if you use a keyed switch, use a "circular" key style switch.

3. The steering lock on factory GM columns offers almost no theft resistance! This is due to the fact that the factory column is just a cheap casting that has almost no strength. There are locking covers that go around the column, but I don't know how well they work.

4. My major concern is keeping the hood closed!

5. Any system has to be something that you will religiously use! Don't get your car stolen while getting that cup of coffee at 7-11.

6. Factory door locks mean nothing!!

7. It's nobody's business how your security set-up works!!!!!! All bragging rights aside, it's supposed to be a secret. The only people that should have that secret are the people that you would be willing to hand your keys to and walk away.

The "Club"; I've never had one, but they look like a good idea. They are very visible and don't require any modifications to the car. I can't help but think that a professional thief could get around one in quick order.

Removable steering wheels; A good idea however I've never seen one that looked like it was constructed well. They require that the steering wheel is located closer to you and you have to use a custom wheel.

Alarm Systems;

"Two wire" systems; These are about as easy to hook up as they go. There is a wire that is hooked to a line that has 12 volts at all times and also a ground wire. They are also not very costly. How they work is that they monitor the voltage that is present and if there is a change, the alarm goes off. When a door is opened, the dome light comes on that that would be cause enough of a voltage change for the alarm to sense. They are armed and dis-armed with a transmitter. The problem is that if the battery is close to the end of it's life, the voltage will drop just by sitting. Some have an internal battery. Thanks to Gene McGill for his letting me know about this type of system. Other than the "old" battery problem, he is happy with the one he has.

Passive arming; This is where the alarm system activates it's self after you get out of the car. What happens is that after you turn off the ignition, the alarm waits for a door to open and close before starting a count down to activation. You still have to use the transmitter to disarm the system. A passive arming system may not chirp when activated. A passive arming system may not work door locks (or power windows).

Active arming; On this type system, you have to use the transmitter to arm and disarm the system.

Alarm options;

"Random code" transmitters; The idea here is that a thief can use a receiver to "capture" the code that your transmitter sends. He then can duplicate that code and turn off your alarm. It really isn't a "random" code that is transmitted. It's a predictable pattern (algorithm) that the receiving unit can anticipate. The receiving unit should except several codes within in the code sequence so that if somebody pressed your transmitter (out of range of the car) several times, the car could still be dis-armed. What it has to do is keep track of the "anticipated" code and the next several codes.

Motion detectors; Make sure that the sensor can be adjusted? Some systems allow you to disable the sensor with the transmitter. I personally don't like motion sensors due to living on a major street. If I had one, it would go off every time a large truck goes by (and piss off the neighbors).

Shatter guards; These are sensors that are "tuned" to the sound of broken glass. They are a good idea, however the sensor has to be mounted where it can clearly pick up the sound. If the sensor is part of the main body, then the main body has to be mounted where the thief can get to it.

Remote transmitter pick-up (antenna); One of the things that I like about the system I have is that the antenna unit is separate from the main body. I mounted it on the windshield behind the mirror so that it gets a clear signal. The wire from it (a standard phone hook-up cable) runs under the headliner trim to where the main unit is mounted.

Power door locks; I feel that this option is a must! By using it, you always know that the passenger door is locked. (even if you always lock the drivers side when exiting, how often do you check the passenger side) Some systems have the required relays mounted in the main unit. Even if you have to add the relays, it's very simple and straight forward. If the car doesn't have factory power door locks, it's a simple modification.

Power windows; I'm not really sure about how necessary this option is, but I'm going to add it. The complication is that a special circuit has to be added that "senses" if the window is already rolled up. This is done be sensing the electrical "load" on the window motor. There has to be a sensing circuit for every window! There is also a timing circuit that gives the window a (settable) amount of time to roll up. The circuits cost about 70 dollars for two windows.

Battery back-ups; One of the things that a thief will do is trash your battery so that the alarm will not work. This can be done by shorting out the battery or even by drilling a hole in the bottom of the battery so that the fluid drains out. The solution is to have a back-up battery that can power the alarm all by it's self. You will have to wire up an "isolator" so that the back-up battery gets a charge and also so that if the primary battery is shorted out, the back-up is protected. You can get a isolator at any RV shop. The back-up battery can be a motorcycle battery or better yet, a dry cell battery.

Voltage sensors; These monitor the voltage levels in the car and could sense when the doors are opened due to the dome light going on. I've never played with these and will have to check it out. Check out the section above on "two wire" systems.

"Threshold of pain" noise generators; It's been quite some time since I've heard of these and they may not be legal (like shooting somebody that has broken into your house in the middle of the night). What they do is emit a noise inside the car that is physically painful. As a result, it hurts the thief while he is inside your car trying to steal it. It's activated when the alarm goes off. (I want one!)

Flashing headlights; I think that the only reason that this may have any worth is due to the fact that it may be easy for the thief to locate and cut the wires to the siren.

Hood Locks;

(Feb 22/99); I've been contacted by a couple people as to where this hood lock set-up can be purchased. The truth is that I got it several years ago and when I went to check recently, I just can't find them anymore!! I seem to recall that I got it at Pep Boys. There isn't a manufacturer's name on the thing, just "made in Japan". I discarded the box a long time ago.

If anybody knows where they can be purchased and who the manufacturer is, please contact me!

As far as I'm concerned, you have to keep the hood closed!! What I've used is a locking cable set-up that mounts to the lower edge of the dash.

It has a circular key lock and also a LED light that can be hooked up to the alarm. The plunger catches on the metal bracket that is mounted to the underside of the hood. You could also have the plunger block the standard hood release from working. If you don't hook up the light to the alarm (or don't have one), at least wire it up so that it flashes so that the thief will think there is an alarm.

At a minimum, get a cable bicycle lock and lock the hood. It may not be pretty, but as long as you get to keep your car, it's worth the ridicule!!!

Tracking systems;

There are two basic systems used for tracking your car once that it has been stolen. Both are only viable within certain areas that have been set-up for the system.

LoJack is a system that is hidden in your car and has to be activated by the police. The problem with this is that you have to contact the police and let them know that your car has been stolen. And then there is the fact that it's up to the police to want to search for your car. If you went to go see a movie and your car was stolen when you went in, the thief would have your car for several hours before you could even call the cops. There is a one time cost for this system. They have their own batteries that have to be replaced by the dealer every now and then. (I don't know how often)

A friend of mine is a Sergeant in the Los Angeles police department and he was involved with the set-up of the LoJack system. He thinks they are the greatest. However;

The only instance I personally know about is when a friend (of a friends) Porsche was stolen from within his garage. It's my understanding (and LoJack can correct me if they want) is that it took 12 (twelve) hours for the system to be activated after the police were notified. The car was located about 2 and a half weeks latter as a striped hulk abandoned on the street!! I don't know if the LoJack unit was still attached.

Tele-trac is a system that works like a cellular phone. It is always active to receive and transmit. It can be activated by the cars alarm system. The car is tracked by Tele-trac once activated (by the alarm). The company "Tele-trac" then tries to contact you to verify if the car is really stolen or not. They then contact the cops. The thief could be caught by the time that your movie lets out!! The problem is that you have to pay a monthly fee for cellular service. It's also possible to wire up the system so that Tele-trac can honk your horn, or what ever you want.

Non-alarm things (and ideas) that you can do;

1. Add a "disable" toggle switch that grounds out the wire that runs from the distributor to the coil. Do this only on a points type set-up. The engine would still crank over, but it wouldn't start. The switch could be hidden anywhere. My feeling is that the thief is sitting in the drivers seat, and as such, the switch should be hidden out of his reach. This makes it harder for you also.

2. I've a battery disconnect switch on the battery that I can use to turn off all of the power. It's an SCCA approved large switch and is under the hood. If I am planning on leaving the car for a long period of time, it's worth the effort of turning the power off and locking the hood. Of course, this means that I need a back-up battery to power the alarm (and door unlock circuits).

3. You could add a hidden switch that is in the circuit that goes to the starter. This would make it so that the starter wouldn't work.

4. Add a switch for an electrical fuel pump. With this, the thief can only drive as far as the fuel in the carb will allow. I'm really not impressed with this due to the feeling that if my car is just around the block, the thief can spend more time to get around the problem.

5. You could add a "line lock" to the brake lines. This would lock up the brakes so that the car couldn't be driven. The problem is that it takes voltage to hold the lock!! I seem to recall that there is a locking unit that you can buy that uses a circular key. This would require you plumbing the brake line to the location of the lock. The locking unit can be purchased from Summit and it is listed in their new catalog. I think the one they have is only for one line (front or rear), but I could be wrong. I have seen one installed that was for both front and rear.

6. Get rid of the factory door lock knobs. These are the ones that you hook up a coat hanger to when you lock your keys in the car. I've seen ones that are just straight and don't have the mushroomed top.

7. It seems to me that it would be possible to add a deflector plate within the door that would prevent the usage of a "slim jim" to unlock the doors. (a "slim jim is what a locksmith would use to get into your car) I have to research this. Although in some areas it's illegal to have a "slim jim", they are easy to get.

8. You can always add a flashing LED to make people think that you have an alarm. They can be purchased at Radio Shack and just get hooked up to 12 volts. Keep in mind that it's going to be flashing all of the time.