Alarms and immobilizers

[ciddyguy]

Earlier this past week there have been some questions on the alarm and/or the immobilizer’s ability to lock (or not) the steering wheel and whether one can set the beeps to arm and/or disarm to be off and perhaps just flash the front lights, usually the headlights or DLR’s if available and sometimes, the turn indicators as well.

In my limited research, I found some information on the immobilizers and alarms themselves, but not how to turn off the arm/disarm beeps on the Fiat 500 and in the process discovered a nonprofit organization called Thatcham, out of Thatcham England that researches security systems, especially for the automobile and certifies them along with installers and categorizes the systems, both the alarms and the immobilizers, by themselves and together as a complete package and discovered that the Fiat 500 is considered by Thatcham to be a category 1 system when equipped with the alarm, which is the top category in their estimation (note: don’t know the specifics of the system in use in the 500 but it appears to have full volumetric/perimeter alarming but not sure if that includes the hood or for glass breakage however and that the interlocks for the steering wheel and/or the automatic shifter are likely served by electromechanical servos/solenoids). Also, I don't know if the Thatcham certification is good outside of the UK but it still bears mentioning here as many people may use them as a reference point for quality security systems and installations.

In this case, take a top immobilizer (a category 2 immobilizer according to Thatcham) and add the top alarm (also a category 2) and combine the two and you now have a category 1 alarm, these are usually built in at the factory level, otherwise, it’s a category 2 -> 1 upgrade where a top notch alarm is added later along with a category 2 immobilizer that’s been installed at the factory, either through the dealer or good aftermarket shop and is properly installed according to Thatcham’s guidelines for category 1 installations, meaning, wires hidden, all joints soldered, the control unit hidden, a battery backed up siren and a L1 fuel valve for diesel cars (in Europe anyway) and trucks and includes full volumetric and parametric arming with anti grab/scanning of the key codes at the very least.

In my research, I found out that there are 2 different versions of the immobilizer, they are, mechanical and electronic/electromechanical and they offer different levels of protection with electronic/electromechanical units being more advanced.

Mechanical immobilizers: they isolate at least one system or more, easy to arm/disarm and have a high attack resistance to a range of hand tools and are permanently or temporarily installed. These often include mechanical actuators for things like the steering wheel lock and/or the shifter lock but are designed to be robust and difficult to penetrate (much like the older interlocks that have been installed in N. American cars since 1969 but better as we all know the original interlocks were easily defeated with the right tools).

Electronic/electromechanical units tend to be more sophisticated and include coded keys with anti grab/scan of key codes and can isolate 2 systems or more and provide an L2 fuel valve for diesels (Europe) and are passively armed and are permanently installed by the factory and are designed into the car from the get go. Many of these systems will also provide a purely mechanical interlock for things like the steering wheel and/or the shifter if an automatic (to prevent it from moving out of park or the steering wheel to be turned).

Many cars built in very recent years now seem to be using electromechanical interlocks for the steering wheel and/or automatic shifter to prevent them from being moved if a breach in the system is detected, or in such instances when remote starting has been activated where equipped. These electromechanical interlocks won’t necessarily activate upon the key being moved to the LOCK/OFF position and removed but will often lock once the car is locked and perhaps will remain locked until the key is turned to the ON/RUN position whether running or not once the system has verified the key is legit even if there is the ignition dis-abler as part of the immobilizer, this allows one to move the car without having to start the car for repairs etc.

But by the same token, if using remote starting, as in the Ram trucks of the past couple of years, the wheel and shifter locks don’t release until one has entered the vehicle via the remote fob or the key in the door lock and performed a procedure, including inserting the key into the keyhole and turning it to the ON position before it’ll release the steering wheel and shifter and then we have the purely electronic part of the system, these will electronically monitor the key for legitimacy, but also will disable 2 or more systems such as the fuel and/or ignition systems or some other related system to further make the car immobile should a breach be detected. These ignition/fuel etc dis-ablers are required for ALL immobilizers these days and have been since the early GM VATS systems of the late 1980’s onward with the vast majority of the systems coming along in the mid 1990's just that today, they are considerably more sophisticated than they were in the past.

Combined that with a top notch alarm that does full interior monitoring (volume) or exterior monitoring (perimeter), including the hood and/or glass etc where equipped and you will have a fully armed vehicle, the best that is available today, as a general rule and it is apparent the alarm/immobilizer installed in the Fiat 500 by either the factory or dealer is one such system, according to the Thatcham group.

To make a good, effective alarm, it has to eliminate false alarms and to alarm when necessary and that IS possible through proper installation of a GOOD system that is properly adjusted for sensitivity as improper installation and leaving settings super high will create false alarms as are cheap systems using cheap sensors/switches and this is especially true of the sometimes super cheap one piece third party after market alarms installed in modern cars as these units sense current draw variances and will set off based on these variances and that’s often the case with modern cars with their breadth of electronics that vary the current draw in and of themselves so false alarms will result with these systems if used in such vehicles, fine for older cars however but are found to be increasingly obsolete and may not be available much anymore anyway.

Conversely, I’m beginning to wonder if the clutch starter interlock doesn’t do much the same thing as the automatic shifter interlock, IE, if there is a breach in the system, even if the clutch is depressed, it disables the ignition system so even compression starting won’t work (much like the shifter interlock won't release if a breach is found as the interlock on automatics is as much a safety device as it is a security device), rather than provide a shifter interlock whereby the shifter is needed to be placed in gear, either first or reverse before the shifter can be locked and/or the key removed, much like SAAB has done with the 900/93/9-3 models where the ignition is placed on the console next to the shifter, forcing the driver to place the car in reverse before one can place the key in the LOCK poisition and thus can remove the key. These older mechanical mechanisms do tend to wear out over time with the accruation of mileage to the point that the key lock tumbler cylinder can’t hold the key in place anymore thus the key can be removed at any point; also it may also prevent the lock itself from working properly due to wear points on the mechanism actuators over time.

And finally, Thatcham has 2 final categories, one is strictly mechanical, a locking device you have to put into place for improved security, things like the Club are considered category 4 devices and after theft devices such as Lojak that help recover the car should it ever be stolen are a category 5 but Thatcham says that category 4 and 5 devices/services are best combined with either the immobilizer and/or alarm systems for a good all ‘round protection but just relying on the alarm/immobilizer may be more than sufficient in many areas.

So in essence, a good, well designed immobilizer system that is part electromachanical and part electronic seems to be the way to a well designed anti theft system that also reduces false alarms when mated to a good alarm that monitors both the exterior and interior of the car and is found to be effective, but no matter HOW well it’s designed, there will ALWAYS be thieves that will use this as a challenge and will attempt to steal cars no matter what, especially if there is money to be had, such as to sell on the black market or for the sum of its parts for others, this is especially true of older popular cars, such as the Honda Accord and the Toyota Camry that didn’t have immobilizers and became easy to break into as they aged to name 2. But in the end, it is really about reducing the potential of YOUR car being stolen or even broken into by removing all valuables from the car to begin with (when possible) and locking your car every time you leave it for a significant period of time so the car can be armed as well. It has been proven that an immobilizer by itself is far, far more effective for reducing outright vehicle theft, reducing insurance claims by a significant margin, while the alarm will reduce what gets stolen INSIDE the car, if not further reduce the car itself from being taken.

One final note, Thatcham.org also will also DEcertify alarms/immobilizers as they become obsolete either through installation techniques thought adequate at the time or simply because it doesn't provide adequate protection through its features or functionality or simply has been found to cause false alarms etc with some older systems still valid (often factory or dealer installed units approved for a particular model by the factory but even some good aftermarket/universal units, properly installed will remain effective over time), but some with a few upgrades can be made effective again according to the nonprofit body but some systems are simply too old/obsolete for upgrades etc and are dropped from certification. Some older factory systems and many of the older universal units are delisted according to Thatcham, but they WERE considered good systems if installed prior to being delisted, often many older universal aftermarket units made prior to a certain point are often deleted more so than the dealer/factory installed units but even SOME systems are now delisted even if just a few years old.