Relay?

I want to install a flashing led (fake alarm) in my car but Instead of of
connecting the led to a 1.5v battery I want to connect it directly to the
car battery (12v) and have it turn OFF when the ignition is ON.

Ignition Led
----------------
Off On
On Off


What relay should I use?

Thank You

Jose

 

I wanted to do this too but I never really thought about how to do it. Also
as a good way to protect your car is you could hook up a hidden switch to
the starter on your car. if the switch is off it will never start. That's
the poor mans car alarm.

Josh

 

Why not just let it flash all the time? It's not like some potential thief
is going to be watching it while you drive!

Cheers!

Chip Shults
My robotics, space and CGI web page - http://home.cfl.rr.com/aichip

 

Doh! Make that the normally closed contact.

 

You don't need a relay. Use a resistor from the LED to
ground and put the led at +12. Then use a diode from
the junction of the resistor/led to the ignition
switch.

-Bill