Picked up a few strips of LED lights for my entertainment stand but the woman didn't approve. Figured Id use em on the truck.

Basically I wanna put the lights under the steering wheel and glovebox because if I drop something on the floor at night, I cant see anything.

Is it possible to simply wire them so that they turn on when I turn on my headlights? I don't want them on with the DRLs, just headlights.

Is it as simple as figuring out which wire draws power when the switch is set to ON for headlights and then tapping my power wire to there?

I'm also open to other suggestions... basically I just want them on when its dark out, and I use my headlights when its dark! (Most of the time )

Thanks

 

The concern is that your CTM controls the headlights. The switch only tells the CTM to turn them on.

Do you have an ashtray light or something you could tap into? It might be the easiest way.

 

If you want the LED's to trigger off the headlights, then the best and safest way to do this is with a 30 amp single pole double throw SPDT relay. You can buy one for less than $10.00 at any parts store or even Radio Shack.

At the CTM on connector #3 there should be two separate headlight output wires. Both are purple/white. One is for the left low beam, the other is for the right low beam. Check with a voltmeter to be sure the wires have 12 volts when you turn on the headlights. Then pick one, it does not matter which one and wire in a relay to control the LED lights.

Tap into the purple/white headlight wire and connect it to terminal 86 on the relay.
Terminal 85 goes to a good clean chassis ground.
Terminal 87 goes to 12 volts fused, I guess 7.5 or 10 amps would be OK on LED's.
Terminal 30 goes to the positive wire of the LED lights.
No connection on terminal 87a.

Then ground the negative wire for the LED's. This way the LED's will only receive power when the relay is energized when the headlights are on. If you pop the fuse for the LED's step it up to 15 amps.

Jimmy

 

Thanks for the replies guys, I don't have an ashtray so I couldn't tap to there, but the goal was to have the lights already on q switch. I didn't want to have to install my own but the more I think of it, it may be easier and more convenient to just splice a power source and tuck a switch under the dash.

I'm just thinking if I wire it to the headlight switch (CTM) I may not like the lights on all the time while I'm driving at night.

Don't ya just love it when you can't make up your mind?

And thanks Jimmy - that was what I was looking for if I decided to go this route, but I'm going to have to do my homework for this relay I may need.

Also LEDS have extremely low power draw so I can't see them blowing a 7.5 amp fuse, it'll all be a question of whats on which ever fuse I choose.

Thanks

 

You said that you got these LEDs for an entertainment stand, is this entertainment stand AC or DC? did the light string come with a power supply? if yes, what's the output voltage of the power supply?

You'll find a lot of these are built to work with 12 volts, but that isn't always the case.

If you're just wiring up some strings of LEDs (the ones labeled for a specific voltage, already have resisters built in so the LEDs don't burn out as soon as you power them up. These resisters are involved in the LED brightness as well as the LED protection), you don't need much since they draw very little amperage. If you want a manually controlled light as you describe, I would look for an "always hot" output on your fuse panel and use an "add-a-circuit" connection to the lights (you don't need a relay for a few LEDs) and then connect that to a switch of your choice, and finally, connect the other wire from the switch to a good ground point under the dash. The fuse wouldn't need to be more than an amp, so it's really there to protect against a short circuit only.

 

I wanted to do kind of the same thing expect on the step boards. how would I wire it into the dome lights