Wiring up LED light bar

[crispins]

I just ordered a 42" LED bar for my roof.

I want the bar on with my high beams.

Where is the easiest place to tap into 12+ when the high beams are on?

Under the hood would be a great spot.

I will be using it to trigger a 40 amp relay.

Do we have a High Beam relay under the hood and if so does anyone have a wirign diagram for it as that would be the best for me.

Thank you much!

 

[crankyjew]

I don't know about under the hood as far as high beam 12v. I suppose you could go directly off of the headlight harness.

Good plan to use it to fire a relay. that's the way to go. make sure you've got an additional in-line fuse on the hot side as well.

On my ST, I used a piggy-back on the interior fuse for the high beams. This method has worked flawlessly on this truck as well as my old ranger.

 

[crispins]

I don't know about under the hood as far as high beam 12v. I suppose you could go directly off of the headlight harness.

Good plan to use it to fire a relay. that's the way to go. make sure you've got an additional in-line fuse on the hot side as well.

On my ST, I used a piggy-back on the interior fuse for the high beams. This method has worked flawlessly on this truck as well as my old ranger.

Is the fuse for the high beams only hot when the high beams are on?

I am wanting my light bar to be on just with my high beams and turn off with my low beams

 

[J_C]

It's not a good idea to hook it up to high beams. High beams are helpful and legal on public roads. Light bars are not legal.

Anyway whether you have a high beam relay or not, you still probably want to tap into the wiring harness between it and the bulb. Take that to the relay coil, using a series resistor to limit current if it's not rated for 12V coil input. Although there are other areas to tap for the main power to the light bar, you might as well just go straight from battery, to an inline fuse immediately after battery, to relay input, then relay output to light bar.

Again I think you shouldn't do this, should instead wire to a switch on or under the dash, or wire it into your fog light circuit instead if you never use them otherwise (as I don't as I find mine practically worthless in fog).

 

[crankyjew]

Is the fuse for the high beams only hot when the high beams are on?

I am wanting my light bar to be on just with my high beams and turn off with my low beams

yes it is. that's exactly what mine does.

It's not a good idea to hook it up to high beams. High beams are helpful and legal on public roads. Light bars are not legal.

Anyway whether you have a high beam relay or not, you still probably want to tap into the wiring harness between it and the bulb. Take that to the relay coil, using a series resistor to limit current if it's not rated for 12V coil input. Although there are other areas to tap for the main power to the light bar, you might as well just go straight from battery, to an inline fuse immediately after battery, to relay input, then relay output to light bar.

Again I think you shouldn't do this, should instead wire to a switch on or under the dash, or wire it into your fog light circuit instead if you never use them otherwise (as I don't as I find mine practically worthless in fog).

to clarify my setup, I piggybacked off of the high beam circuit through a switch on the dash, to fire a relay which controls 12v directly off of the battery, with an in-line fuse, to power my light bar.

now I happened to use a factory ford fog light switch, which is a little odd (it switches the ground side, not hot). this made my wiring a little more complicated, but the concept is the same. With the high beams off, my light bar switch does nothing. with the high beam circuit on, my light bar switch control the light bar through a relay directly off of the battery.

I had a very similar setup on my old 02 Ranger, neither have ever given me trouble or a reason to do it a different way. full disclosure, I live far enough in the country to use my light bar on the road all the time. being on the high beam circuit and quickly controllable with the high beam stalk is nice.

 

[crispins]

It's not a good idea to hook it up to high beams. High beams are helpful and legal on public roads. Light bars are not legal.

Anyway whether you have a high beam relay or not, you still probably want to tap into the wiring harness between it and the bulb. Take that to the relay coil, using a series resistor to limit current if it's not rated for 12V coil input. Although there are other areas to tap for the main power to the light bar, you might as well just go straight from battery, to an inline fuse immediately after battery, to relay input, then relay output to light bar.

Again I think you shouldn't do this, should instead wire to a switch on or under the dash, or wire it into your fog light circuit instead if you never use them otherwise (as I don't as I find mine practically worthless in fog).

Thank you but I do not need basic wiring instructions.

I live in the rural mountains of TN, I want my lightbar on with my high beams.

Why you would recommend I connect it to the fog light circuit which is only on with the low beams, that seriously makes no sense and makes me think you have no idea what you are talking about?

Also you mention using a resister in line before the trigger to the relay, why? I thought you might be from a foreign country but your profile says KY, what relay do you think I would be using that was not rated for 12 volts?

 

[crispins]

T

yes it is. that's exactly what mine does.



to clarify my setup, I piggybacked off of the high beam circuit through a switch on the dash, to fire a relay which controls 12v directly off of the battery, with an in-line fuse, to power my light bar.

now I happened to use a factory ford fog light switch, which is a little odd (it switches the ground side, not hot). this made my wiring a little more complicated, but the concept is the same. With the high beams off, my light bar switch does nothing. with the high beam circuit on, my light bar switch control the light bar through a relay directly off of the battery.

I had a very similar setup on my old 02 Ranger, neither have ever given me trouble or a reason to do it a different way. full disclosure, I live far enough in the country to use my light bar on the road all the time. being on the high beam circuit and quickly controllable with the high beam stalk is nice.

Thank you bro! I will tie into the high beam fuse.

 

[crispins]

I picked up a radio bezel from a Sport with the second switch on it (used for the rear window heater)

I am going to use that to be able to turn the lightbar off if I want to for some reason.

I still cannot come up with a reason why I would want to do that but if I ever do I will be able to have the High Beams on with the lightbar off.

 

[N2FORD]

That sounds like a good plan. I was think if you did a flash to pass or flash to let a big rig over you wouldn't want the light bar to flash.