Car alarms are generally pointless. Unless they've got "hard cutoffs" for critical systems, it's just going to make noise as they drive away (don't laugh, I've seen it happen!)
A cutoff for ignition and/or fuel would work to an extent - if they really want your rig, they'll come back with a truck - but it will stop the casual thief. If both ignition and fuel delivery are to be cut off; the switches should be separate (ideally) and either camouflaged or hidden in separate locations.
Motion-activated lamps and cameras are going to be more useful than a car alarm - they'll start recording immediately, and usually send the freelance socialist running as soon as they come on (IR cameras are nice, but lack detail. You want good facial detail? Use visible light. Suggest you mount the camera - and the lamps, if possible - well up out of reach and behind some sort of protection. Expanded metal is good for this - for the camera, you can cut a hole for the lens to look through and maybe even weld a collar around the cut hole so they can't readily bend the metal.)
There's no way to stop a determined thief. Period. Full stop. The old saying goes that "locks only keep honest people honest" - although they'll stop casual thieves and thrill-seekers as well.
I've often had to work in "rougher" neighbourhoods, so my security needs are mobile. What I've done to secure my truck:
- START function removed from the keyswitch, and routed to a separate toggle. You can crank the key all day - it don't do nothing.
- Separate fuel and ignition cutoffs, using magnetic reed switches and latching relays (you can't even see the switch, the only way to trip it easily is to wave a small magnet over it. Guess who has a small magnet, and knows where to wave it?)
- Pressure switch under the seat (I'm a big guy - the average punk kid out here is about half of me. If you don't have enough weight on the seat, even kicking on the cutoff switches won't work. If you don't weigh enough, it won't do you any good to know where the switches are - since they get power from the pressure switch anyhow.)
- I've also redone the ignition switch wiring harness - all wiring in that subharness is 14AWG black, so there's no visual clue how to hotwire the thing.
No, I'm not going to tell you where the switches are. There are three people that know where they are (including me) and only two people who know where the bypasses/overrides are (including me.)
Locating the switches I shall leave to you as an exercise in creativity - but either camouflage them so they blend in, or stash them so they're out of casual view (or both.)
Other things that can be done?
- Rig a keypad on the dash that trips a latching relay when a combination is entered. This relay can complete the circuit for fuel, ignition, or both.
- Install a fuse or relay block for a critical component somewhere that's easy to reach from the driver's seat (like an additional fuse for the fuel pump.) Take the fuse/relay with you when you exit the vehicle.
- Take a critical component (ignition rotor is common) with you if you're going to park for a bit. Time-consuming, but it works.
It really depends on what threat you're planning on facing, and where it will be in relation to "home" and "work." Having a bypass/override switch in place in case your security device goes pear-shaped on you won't go amiss, but keep that information close-hold as well (see prior comments.)
Once you do something like this, bear in mind that it's in the same league as carrying a concealed sidearm - the idea behind keeping it concealed is that no-one knows it's there unless you need it. Why are you hiding the cutoff switches? So no-one else knows about them! That's why I'm not going to tell you where to put them - just put them somewhere that is:
- Relatively hidden (through camouflage or concealment)
- Naturally easy for you to reach.
- Reachable with a natural motion (if you have to reach out of the way, you'll give it away on your own! Knowing that there is something there to find makes it more likely that it will be found and defeated)
- Easy enough to service (because, as you should know, electronics do wear out and want replacing from time to time...)
- Somewhere you can bundle the "security" wiring in with the OEM wiring, so it doesn't look out of place (that way, it will look more like a recent repair than something you've added.)
There's no such thing as "100% Security," but you can make it more difficult and get the "convenience thief" to look somewhere else. Yeah, a manual can be shoved into Neutral and pushed away (I have a manual in my rig,) but how long does it take to drop the rear driveshaft on an auto? And that's from under the car, so you're not likely to see it happening.
However, with a little creativity and minimal work (really!) you can address most common threats in your area, and do so in a cost-effective manner (the most expensive thing I had to get, years ago, was the pressure switch. Pretty much everything else came from Radio Shack, and I think I got it all for <$20, cash in hand, tax included.)
In a way, these days, having a manual transmission provides its own security device - there are fewer and fewer people who know how to drive them! I'd still like to get a five-speed that I can put Lightning Rods on, do a D300 with a twin-stock (or maybe an Atlas?) and have mechanical selectable lockers fore and aft. I'd have a forest sticking up out of the transmission tunnel - no-one would want to even try to figure it out! Let's see:
- five levers to operate the transmission (four for a four-speed, six for a six-speed. But, most Lightning Rod setups I've worked with have been five-speeds)
- two more levers for the transfer case.
- one lever for the front axle
- one lever for the rear axle
That would give me eight (four-speed,) nine (five-speed,) or ten (six-speed) levers sticking up in the middle of the truck!
Lightning Rods are easy enough to operate, if you know how. Most people do not - which will give me "security through obfuscation." That, and it can make shifting quickly (when needed) and rocking the vehicle (also when needed) much easier than it is with the "H" or "modified H" pattern usually in use...
