Headlights Harness Upgrade + DRL

[Hamzahng]

Hi all,

this is my first post on this forum. so I thought to introduce my self first. I am Hamzah, and I am from Dubai. I have an american import '98 XJ.

I have recently bought a 55W LED Headlight. and it has a DRL Pin which I connected to the Parking lights. they are running nice except that the left Low Beam is always flickering, and the DRL is not turning on at all .

I have been reading online for a solution where I found that there is an upgrade kit which consists of a couple of relays and it connects to the light to give it the full power. I have decided to make one on my own since I am and Automation and Electrical Engineer. I have all the circuits drawings with me but I don't know how to upload them here

now for the questions:

I was thinking of the Parking lights, whenever you are using the blinkers they will start blinking therefore it will be redundant to use them. so I want to connect them in an inverse connection with the Low Beam lights therefore whenever the Low Beam is off, the DRL will be on. but the problem with such a design is that whenever I turn off the car, the DRL will always stay on. to fix that issue I decided to connect a relay that is coming from the Ignition Switch. << How can I do that ... can anyone help me in connecting a relay to the switch so whenever the car is on the relay will be on, thus the DRL can go on.

or if anyone as a better idea on how to connect the wire for the DRL to follow the above logic.

Thank you guys.

 

[RedHeep]

If I was looking for an ignition on 12v power source to trip the relay, I would use one of the existing open slots in the fuse panel under the dash. Use your meter to find an open fuse slot that is only energized when the ignition or accessory is on and then use an add a fuse adapter to run that power wire to the relay terminal that trips the relay.

Any wires that you tap into in the engine compartment may or may not have the capacity to run another circuit. Your relay power should always come from the battery, especially if you're going to run an upgraded headlight harness.

 

[Jeep Driver]

You NEW wire harness for the headlights is an independent circuit with it's own power source which is hot all the time. Whatever signal is sent to the relay.......daytime running or otherwise......the new circuit responds to.

You use the ends of the existing headlight circuit to trigger the relay of the new circuit, nothing changes, lights operate exactly as they do now.

The benefit of the new harness is, heavier wire, shorter path, and the load is no longer going through the headlight switch.

 

[RedHeep]

I think he understands what an upgraded headlight harness does. He's asking about how to turn on the separate daytime running function of his LED headlights, which is completely separate from the circuit that turns on the high and low beams. You still need an independent signal from the ignition source to trip the relay for the DRL's unless you only want them on when the headlights are on, which is what the original switch and new harness does.

 

[Jeep Driver]

Well then, if he want DRL to be on when the engine is running..........run that relay to any ignition source under the hood. Tap into any wire that is on when the ignition is on, pretty much a no-brainer.

 

[Jeep Driver]

Lights, fans, are always wired directly to ground, ground does NOT pass through the relay.

There are two triggers to a relay, pos and neg.

Pos is triggered by headlights or ignition or ...............

Neg can be triggered by a switch on the dash.


My lights, light bar for example, is triggered on the POS side by the brights switch, whenever I need the light bar I just hit the brights. If I don't want the light bar to be triggered I simply turn off (disrupt) the neg trigger on the dash, flip the switch.


He can do the same with his DRL, POS trigger by ignition under hood, NEG trigger by switch on dash, if he wants to sit in the dark with the engine running.........just disrupt the neg side of the circuit.