Replacement LED headlights with support for built-in DRL

[dan5150]

Apologies if this is a FAQ. I used the very usefull search function and didn't find exactly what I was looking for.

My '99 TJ was build for the Canadian market so it has built in daytime running lights. They work fine.

However, the stock halogen bulbs are pretty dim in comparison with every other modern car on the road. ;-)

Researching options for replacement LED's, and the ones that support DRL, all seem to want you to splice into the side marker or running light harness.

Since mine already has the DRL "built in" is there a way to install the new style LED's and have them leverage the existing harness? Basically, just plug and play?

 

[Chris]

Not to be obtuse, but why not just eliminate the DRL feature entirely and go with some standard LED headlights?

That would be what I would do.

That being said, any headlight should work. I suspect all you have to do is splice in a wire.

 

[dan5150]

Thanks Chris. That is a possibility. I like the feature, how it automatically turns on/off without the driver having to think about it.

However, I am more interested in having useable headlighs.

So if i were to buy one of the many recommended LED headlights and plug them in, they should work but I just loose the DRL feature, right?

 

[byarnell05]

Pretty sure most of the headlights that have a separate dedicated light for DRLs are going to need to be spliced in because the factory DRLs (I could be wrong here) actually run the high beam circuit at 50% output. I have JW Speaker headlights in my TJ that has factory DRLs and that's how they run.

 

[hear]

Thanks Chris. That is a possibility. I like the feature, how it automatically turns on/off without the driver having to think about it.

However, I am more interested in having useable headlighs.

So if i were to buy one of the many recommended LED headlights and plug them in, they should work but I just loose the DRL feature, right?

Ive thought about this, the easy solution is to just wire a headlight relay to a switched 12V, but then you'd have to have the key on to have lights, which you might not want. So you would need a more complex circuit to be able to give them power w/o the key as well. I would not mind having DRL for my kid's jeep.

 

[lBasket]

I just turn my headlights on every time I get in my jeep

 

[dan5150]

Thanks to all that have replied. Super helpful!
I just installed a set of LED's I got off Amazon. Mainly just to test the behaivor and to enable me to drive a little at night.
These do a have a separate wire for the DRL's which in these lights are a separate small set of LED's. I didn't hook anything up to up to it, and just connected them to the existing headlight connector. As a few of your pointed out, as soon as I started moving, the DRL controller kicked in and lights came on.
I will take a drive tommorrow evening to see how well they work and how bright the DRL's are (presumably 50% power to the high beams).
Just in my garage they WAY brighter than the stock halogen's.

 

[dan5150]

Update on this. Problem Solved!

After more research and studying of the wiring diagram from the Haynes repair manual, I figured this out.

Quick recap:
My '99 TJ was built for the Canadian market. (Confirmed by looking up the build sheet, found by using the link listed in the "How To" section of the forum).
Apparently, the Canadian builds have daytime running lights, controlled via a DRL module mounted on the firewall. (See pic).
The DRL's work by detecting the vehicle moving, then turning on the high beams (at half power, I think). No movement of the headlight switch, they just come on.
This works "fine" with the stock halogen headlights, but when you replace the bulbs with LED's, half power brights, is the same as full power brights. Plus, many LED bulbs do have separate DRL lights/modes that are often enabled by splicing into the parking lights.
I wanted to figure out a way to leverage the same built in DRL module, with the DRL lights in my new LED headlights.

Solution:
Easy. Find the DRL module mounted on your firewall. Unplug the harness and pull back the loom. Find the RED/ORANGE wire. Cut it, and connect the wire to your DRL lights to the side that goes into the connector. Not the side that goes into the harness. Done.

My DRL mode in my LED headlights now automatically come on, and my headlights and brights work normally via the headlight switch.