I bought some Oznium LED strips and I am hooking them up to a switch that can hold two strips at a time, so I am pretty sure the pic: http://img329.imageshack.us/img329/9092/circuitqa1.jpg is what I should do. Where do I put the negative wire for the LED though? Thanks for any help!

 

Usually the negative wire from the LED strips is connected to ground (metal part of the car)

 

I tried that and it didnt work, I also tried stripping off ~2in and tying it around a bolt and putting electric tape on it and still nothing. The only time they light up is when connected to a 9v battery. Would I be able to hook up the strips to the fuse box then solder the negative onto the ground of the 9v? Or would that cause some problems? Thanks!

 

you must not have a good ground then. Or your 12V wires are not connected to 12V.
As for the 9V battery, that would be a floating ground and will not make the lights turn on. You need 12V and ground from the vehicle to complete the circuit.

 

Yep,. the positive powering the leds needs the same reference ground as the battery. You dont have a good ground and/or power connection.

 

Go to radio shack and pick up a ring terminal - this will crimp on the end of your wire and allow you to put it around a screw like you tried. Often taking a wire and wrapping it around a screw will not give a solid ground. Also make sure that your 12v lead is good. All your connections must be tight, not just simply touching.

 

I am betting if the power side is good, the screw he is using is not grounded.

 

did you switch wires around?

 

Went to Radioshack and got some ring terminals and used the screws by the dead pedal to ground the LEDs. Worked great! Thanks for the advice enjoithis and thanks to everyone else for replying

 

Glad it worked for ya.