ok, so i bought 8 small LED's already in a circuit at autozone for like 10 bucks.. it says it needs to be hooked up to 12 volts, and i don't particularly want this running off a 12v battery that i will constantly have to be changing.. Where can i hook this up to so i'm not giving it too much power? also, i've noticed that a lot of people on the forum who have done this mod just use a switch to turn them on and off.. i would rather hook them up to the dome light so that when i open my door or turn the dome light on they come on.. does anyone know how i would go about doing this?

 

if you want them to function exactly like the dome light, the only thing you can do is hook them directly to the tabs in the dome light that contact the bulbs.


OR, you can wire it to either turn on when the doors open or turn on whenever you turn on a switch you install.

take the positive wire lead and run it to a constant 12V source (12V even with the keys out... you can find a wire that does this at the wiring harness connected to the back of the radio).
Then run 3 separate wires off your negative lead. Run one wire to a switch. Then run that switch to the ground wire on the radio wiring harness. Then take one of the other wires and run it to the dome light switch located in the driver door jam. Then run your 3rd wire to the switch in the passenger door jam.

The only abnormality with this setup is that when you turn the switch for the LEDs on, the dome light will turn on too. To correct this, simply turn off the dome light when you turn the LED switch on.

Visual Aid:

 

wow.. that was a perfect answer, or at least for me. Ive been looking up how to set it up to turn on with the door, and everything ive seen has been soo complicated. Haha, ima bookmark this lol.
And tarheels131, you dont need another random 12v battery. If you want the switch, you can hook it up to the harness (probably easiest), or you can send the power to your regular battery, but then you need to fuse it, and ground it on the chasis anywhere. It will not drain your battery as long as you keep it turned off when the cars not on.

I would do exactly as trustdestruction said. That visual aid is powerful too..
But yeah, you dont need to worry about draining any battery, just dont leave them on when the cars off or you will drain the battery lol.

 

just for the record, an LED will take a very long time to drain your battery, so if you leave it on don't worry about it.

point and case: many cars have a blinking anti-theft LED, and car alarms have a blinking LED. Their batteries don't go dead from that.

I just would try not to leave it on, because at night it can attract attention to your car since the floor inside will be glowing and visible from outside of the car.

 

best way to hook them up. thats how i have mines set up. turns on when i open the door and turns off when i close the door. i also have a switch to turn the lights on and off, obviously only works when i have the doors close