Relay circuity

[GeneralNoobzor]

I'm installing 4 strobe lights in my engine bay to keep the pack rats out.

If I hook them up to a relay that has a closed circuit when the vehicle is powered off, where would I get the signal wire for that?

The only thing I can think of is the alarm led signal.

 

[JKmotorsports]

If you ground #85 and run #86 to an ignition source, that will open contacts 30 and 87a while vehicle is running and will close those contacts when off. Use 30 as your power source from battery (with fuse) and 87a to the + input of the strobe. This will power your strobes everytime ign is off. The battery will probably not last like this though in between alternator charging, unless you keep it trickled charged while engine is off.

 

[GeneralNoobzor]

http://tinyurl.com/m3hok3y

These things have such a small draw, I am sure an optima yellow cap will be okay :3