im putting 8 LED's into the cab of my truck,i want them to come on when my lights are on........couldnt i just run the positive to the number 7 fuse in the fuse box(lights fuse) and then ground it or would it have to be a switch of some type?? thanks for ANY HELP U CAN GIVE

 

You can't use fuse #7 because it is for a trailer brake/turn lamp.

Fuse #33 in the underhood box protects the dash night illumination circuits.

If the LEDs are intended for a 12v system and already have current-limiting resistors, you can wire them directly to 12V power and ground (observing the correct polarity, of course). If they don't have integral resistors, you will need to add them.

LED Tutorial

 

the leds i have are in a kit and come pr wired and all .....it says hook to a 12v postive and the to a ground what im lookin for is a way that when i turn my headlights oin they are on also.....would fuse 11 work? (gauge cluster,4x4,main lightsect.....)im just lookin for a fuse that when i turn the lights on they leds come on................

 

You need to tap in after the headlight switch so it can turn them on and off. Right at the fuses, it's usually either hot all the time or hot in certain ignition switch positions.

If you tap the solid brown running light wire, the circuit will have full system voltage whenever the headlights or parking lights are on. Look for the brown at the headlight switch, dimmer module or the GEM.

The light blue/red is for dash illumination and is modulated by the dash dimmer. I don't know how your particular LEDs will react to the dimmer though. You can find the light blue/red at the dimmer module, cluster, radio harness, HVAC controls, etc.