power question, i need power for my cooling fans Options

[whitefuzz]

FINALLY i have a holiday! (3 weeks)
so now i have the time to take care of the setup of my trunk i've been planning for a while now

still have a question:

my amps come under plexiglass
that will look sweet but that way they're also in a little box witch will get filled with hot air once the music starts
that air should get out so i got some nice pc casemod cooling fans

now i m wiring these

they should start spinning when the radio starts to play but i can't put em on my remote cable
so i m now looking for a cable in the car that has power when i start the car
en goes back to nothing when i shut down the car...
that way the fans will start spinning when i start the car & stop when i shut it down...
that should give the amps a nicely cooled "box"

now my question : where can i find that wire?
doesnt really matter to me wich one
but it should have power when the car starts en return to nothing on shut down...

i thought about the cig lighter cable (cuz i'm removing the cig lighter and replacing it with my remote bass control button) would this be a good idea?

[jontechie]

If you want your cooling fans to only be in operation when your radio/head
unit is active, then how about using your systems auto antenna drive
line to trigger a low power relay.The antenna line will only become active when your system is switched on, this can be used to drive the relay coil.
The power feed to the relay switcher can be fed from a tap behind the cigarette lighter socket or direct from your power line feed to your radio unit. The cig/Rad power feed is 15 amp rated so should be adequate. Also make sure you connect the fans the right way round, remember you want to extract hot air from your enclosure, at the same time your enclosure should have vents to allow cooler air replace the warmer air being extracted,

Jon