Stupidly easy "pretend" alarm LED

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Robsey
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Stupidly easy "pretend" alarm LED

Post by Robsey »

Hi all,
After reading about a new member whose car had been broken into,
I got to thinking of adding a very cheap / simple deterrant that looks like an alarm LED on your dash.

As far as I am aware, all Cavaliers have a "P" pin position on their ignition switch.

P is for "Parking Lights".
So if you put your indicator stalk to the left turn position with the ignition off, the side and tail light for that side will illuminate.

Put the indicator stalk to the right turn position and the right side and tail lights illuminate.

Apologies if that is old news.

It's function in the UK is that if you park on a street with a speed limit above 30 mph after night-fall, then the side and tail light nearest the road should be illuminated, to allow passing vehicles to see your car.

So I shall now get to the point.

Pin "P" of the ignition switch is only live when the ignition is off or the key is removed.

So you could wire the anode (positive leg) of a flashing red LED to the "P" terminal of the switch.
Of course we are talking about an led intended for use at 12 volts.
The pin on the ignition switch connector is the one with a grey wire on it.

And the Cathode ( negative leg) to any ground point on the car.

So what happens is -
When you turn off the car and / or remove the key, the LED will flash giving the impression that you have an alarm fitted and active.

Most people have a working alarm by now due to the Cavalier's notoriety for being one of the most commonly stolen cars in the 80s and 90s.
But for those that don't, it is a cheap gimmick that may put off the opportunist thief.

As a sub note - you could of course use any colour LED, but most people 'expect' an alarm to have a red flashing led.
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Cavalier342
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Re: Stupidly easy "pretend" alarm LED

Post by Cavalier342 »

Very good Robsey, however I have fitted a £0.99 flashing LED light in my old car wired to the cigarette lighter plug, which is permanent live, and that does the same job, takes 5 minutes to fit.

But the best defense against car thieves/low life pathetic scumbags looking to break into cars in a dire attempt to feed their drug habit is a simple baseball bat with some long rusty nails on the end of it.
Previous:
China Blue 1989 Vauxhall Cavalier L 18SV
Kings Blue 1992 Vauxhall Cavalier LSi Auto C18NZ
Smoke Grey 1994 Vauxhall Cavalier V6 C25XE

Am I a light sleeper or a heavy sleeper? Well that depends on how much I've had to drink...
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Robsey
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Re: Stupidly easy "pretend" alarm LED

Post by Robsey »

True - rusty nails do sound a great solution for those "wastes of space" that have no respect for other peoples property.

Sadly it is not strictly legal / permitted to keep such a tool to hand, as it would look like you are "going equipped" with an "offensive weapon".
Damn the legal system!! - ha ha.

I suppose in my O.C.D. sort of mind, it looks more "believeable" if it only lights up when the car is locked up and tucked up for the night.
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Mk3alan
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Re: Stupidly easy "pretend" alarm LED

Post by Mk3alan »

Didn't know about the ignition live when off! I have a switch under the dash that powers a flashing led - it's been flashing for the last 20 years, I also use a stop lock device that fits on the steering wheel.
2 visible deterants that hopefully will direct any scumbags elsewhere.

Alan
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James McGrath
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Re: Stupidly easy "pretend" alarm LED

Post by James McGrath »

I'm lucky that I live in a low crime area.
Last time anything happened here was when, in a fit of rage, Miss Norris deliberately trod on Miss Petunia's flower bed in 1976.
It's still the talk of the town today.

Still a tempting idea though.
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Robsey
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Re: Stupidly easy "pretend" alarm LED

Post by Robsey »

In murder she wrote, or one of Agatha Christie's novels, Jessica Fletcher or Miss Marple would be living in such a village.

No car crime to speak of, but murder in the moonlight seeking revenge for down trodden flowers by the scullery window.

:o
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Cavalier342
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Re: Stupidly easy "pretend" alarm LED

Post by Cavalier342 »

:lol:

I firmly believe that the best form of defense is offence, always has been, always will be.
Previous:
China Blue 1989 Vauxhall Cavalier L 18SV
Kings Blue 1992 Vauxhall Cavalier LSi Auto C18NZ
Smoke Grey 1994 Vauxhall Cavalier V6 C25XE

Am I a light sleeper or a heavy sleeper? Well that depends on how much I've had to drink...
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