Flashing LED (simulated car alarm) wiring

[eddiev9]

I got one of those flashing LED's off eBay (simulated car alarm)...

There's a white wire (constant 12V+)...okay
Then there's a black wire (12- ground)...yup, makes sense
Finally, there's a yellow wire that says "connects to any 12+ Accessory Wire for the 12+ when the ignition is on"...Huh? Sounds like the ignition has to be on for the LED to flash, but why would you want to start the car for it to flash? Shouldn't it be the other way around?

Would anyone happen to know which wire I need to tap into for the LED to flash the moment I turn OFF the ignition?

In fact, are there really black, white, and yellow wires in there that do what I want?

 

[SoDakJeep]

Could It Be That The Yellowwire Would Activate A Kill Switch Or Resistor Of Some Sorts????? When You Turn On The Key It Sends The Power To Flip The Switch Hahaah Idk....never Was Good With Electronics

 

[JC]

I'd test it with the yellow wire to the accessory to see if it does what you want. If it does, you're ok. If not, you can go to the parts store and get a cheap relay and wire it to supply power to the yellow wire with the acc off.

 

[MoladoGuy]

Well it sounds like the yellow wire will turn the LED off when you turn the car on. Who wants the flashing LED when you start the vehicle up? Reverse polarity or something?

 

[Marlon_JB2]

My advice: Get a real alarm. Thieves don't pay ANY attention to flashing lights.

 

[azmotoman]

Better yet, get one of these and install it on the starter cable:
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=92688

 

[eddiev9]

I can't think of anything that activates when the ignition is shut off. I wonder if I could somehow tie it in with the factory alarm where I press Lock and the LED flashes...but I have no idea where to look. Suggestions?

 

[OldBlue]

Actually, if it works like I think it does, white goes to constant 12V+, black to 12V-, and yellow to switched 12V+. When the ignition is on, the yellow receives power, turning the power from the white wire to the LED OFF (like a relay, but w/o the actual relay). When the ignition is OFF, the yellow wire gets no power and it then allows power to flow through the white to power the LED.

 

[eddiev9]

Actually, if it works like I think it does, white goes to constant 12V+, black to 12V-, and yellow to switched 12V+. When the ignition is on, the yellow receives power, turning the power from the white wire to the LED OFF (like a relay, but w/o the actual relay). When the ignition is OFF, the yellow wire gets no power and it then allows power to flow through the white to power the LED.

That would be my guess, too. I just can't figure out where that "yellow" wire would be, though. I'm thinking of simply going with a tiny flip switch. I don't want to start stripping and tapping into wires for hours in this 100 degree weather.

Anyone know where I can find a tiny switch? Kind of like a kill switch for a real alarm would be ideal.

 

[razzerx]

The yellow wire shuts it off when you start the vehicle.

 

[Tline155]

Yes this is a simple relay built into the LED, The White and Black wire are the main circuit and apply power to the LED. When the yellow wire ir hot (vehicle on) the relay switches and OPENS the white/black circuit and cuts power to the LED. I have a degree in electronics and it is a simple transistor circuit or just a bridge.

You just need to connect the Yellow wire to any switched wire in the fuse pannel, even the radio has a switched power and a constant power. Having a volt meter would be easiest to find a switched power wire.