Wiring for a fake alarm led

[stoop]

I am going to install one of those flashing led's so it looks like the truck has an alarm. Does anyone know where to find 12 volts that is only powered when the truck is off? If not I know how to use relays in order to make it work, just looking for the easy road!

 

[Wicked_Sludge]

why not just hook it to a 12volt constant? will it hurt if it flashes while your driving?

 

[MAKG]

There is no voltage source that is only active when off. However, perhaps you can find and install a normally-closed relay.

Or maybe buy something that isn't a flaming POS. Negative logic isn't hard to figure out and if its THAT badly engineered, do you really want to put it in your electrical system?

I doubt a flashing LED is going to fool anyone. No one pays attention to alarms. Everyone knows that.

 

[daniel3507]

my brother got one for his jeep and decided he didnt want it. i got bored and decided to put it in my truck. took it out the next day. they get really annoying when driving at night so i wouldnt recommend them

 

[RobbieD]

Very simple connections to do this. Get a 12 volt flashing LED (Radio Shack carries them; get one with preinstalled wire leads). Connect the LED's (+) lead to constant (+) 12 volts; connect the LED's (-) lead to switched 12 volts (either ignition or accessory). Both connections can be made at the fusebox. The LED will flash when the ignition is off, and not flash when the ignition is on. Make sure that you get the 12 volt flashing LED, not a 5 volt.

 

[MAKG]

And DO NOT GROUND the LED. You won't like the results.

Ignition off doesn't necessarily ground the ignition lead, but it often does.

And make DANG sure there is some resistance in that circuit or you'll short your ignition to ground.