Thread: Car Alarms

Originally Posted by Tins

Years ago I experimented with a lockable non return valve in the braking system on a FIAT. It worked, as as soon as the brakes were applied they wouldn't release. I imagine such a thing would be frowned upon now. Probably was then, if I think about it.

My old (1955) Jaguar Mk VII had something similar. It was a solenoid valve on the rear brake line that held the rear brakes on until one touched the accelerator. It was great when facing down hill in Drive, the car didn't roll forward when one removed one's foot from the brake pedal.

I know this won’t stop the vehicle being stolen,but in our old Mitsy work vans we used to have a hidden waterproof external switch located in a hidden position outside the vehicle.
We wired it into the common door switch wiring with a latch in relay that kept a hidden very loud siren going until either the switch was turned off or the battery disconnected.

The newer vehicles we don’t worry about as they have their own system.

In another life,working for a large AC company all the work vans had a module mounted on the dash which we had to enter a code into to open a solenoid in the fuel line.
They only fitted these after a couple were stolen and one was used in a bank robbery.
The company carried its own vehicle insurance.

I reckon a secret kill switch on the fuel pump circuit. Similar on the starter has more limited deterrent features as the battery is relatively close to the starter for hot wiring.
Overly loud alarms are illegal, heavens to Betsey, we can't be injuring criminals.
I had a mate who owned a workshop. He was broken into, by cutting a hole in the tin wall, from the adjacent, vacant shed. The shed was repaired and tools replaced by the insurance company. Six weeks later the exact same thing happened. The police said it would have been the same crooks, they know it takes six weeks finalise the insurance claim.
My mate, John said that in six weeks, he and I would be waiting in the shed, with a bottle of rum and baseball bat each . The cop said that if we did so, we'd both be charged!
John's brother landed a job, selling alarms. The top of the range model was so loud, it affected people's balance. John had two fitted, diagonally opposite each other.
A month later, they were recalled as illegal. Apparently the owner could be charged with multiple offences, including assault and deprivation of liberty, if the alarm hurt or disabled a trespasser.

Originally Posted by V8Ian

A month later, they were recalled as illegal. Apparently the owner could be charged with multiple offences, including assault and deprivation of liberty, if the alarm hurt or disabled a trespasser.

You can be charged if your dog attacks an intruder. What do the cops tell you to do to deter burgs? "Get a dog".
Man traps of any kind are illegal as well. Doesn't stop our betters from having armed security though.
And if your car does get stolen, nothing is done. The only reason to call the police these days is to get the insurance report. Might as well take up a life of crime.

Originally Posted by V8Ian

I reckon a secret kill switch on the fuel pump circuit. Similar on the starter has more limited deterrent features as the battery is relatively close to the starter for hot wiring.

Older cars, like TDis etc, have mechanical pumps... Suppose a solenoid valve might work. So long as you don't forget it. Bugger having to bleed it every day

Originally Posted by Tins

Older cars, like TDis etc, have mechanical pumps... Suppose a solenoid valve might work. So long as you don't forget it. Bugger having to bleed it every day

Bleeding is less of an inconvenience than walking, unless it is bodily.

Most thieves want to be in and out as fast as possibly with as little drama as possible. Any alarm that is sufficiently loud will deter them from poking around the wiring trying to figure out how to turn it off. The same goes for any immobiliser that prevents them from driving.

A loud alarm on the outside with a dito (just within legal limits) siren on the inside that can't just be ripped off or shut down, alarm lights, heck even highbeams flashing that pulls a lot of attention wherever they go, a solenoid valve in the fuel line in a not easy to reach place which causes the engine to die very quickly after setting off, all sorts of things can be thought of.

Personally I am looking into a deadman switch or something similar to keyless entry for my car in case of carjacking. They could get in and drive away but the car would automatically stop a few hundred meters down the road. Too far away for them to still shoot me but I can just walk back, get in, start and drive off.

If thieves are bypassing immobilisers / alarms they would be known systems. Use or make something unusual and you are too difficult to steal from. Only problem with that is: I once glued a radio in after it was stolen twice for a mate and the thieves were so ****ed that they could not get it out, they stuck the screwdriver in the display. Petty -bleeeps-

-P

Hi John,
For your OKA I would use multiple things.
Switch in the fuel solenoid circuit.
Cut off in the fuel line, manual or electric, or both
Switch in the starter circuit.
Alarm
GPS tracker.
A couple of Apple air tags, given your an Apple person.

You could probably hide the switches in plain sight in an OKA or Defender, just add them to a bunch of other unlabelled ones.
A manual fuel tap you could put between the seat ans engine cover, no one would know what it was.

That should be enough to confuse anyone.

It would take discipline to use them all the time.

Tony