Here is my conundrum, I currently have HID xenon headlights installed by the previous owner (low beam only, more on that later) on my 1988 XJ Laredo and one of the bulbs died so I want to make the jump to LED high/low compatible headlights. The issue at hand is the OEM headlight sockets have been removed because the HIDs are all hard wired to the battery, to a relay and to the ballasts, so I can’t just get a putco harness and plug-and-play because it has no source plug to power it. I need to figure out how to rebuild and properly wire a single headlight socket so I can install the new harness and wire everything so the plunger switch on the dash and the dimmer on the steering column work like they should. I have been searching and reading for a week now and cannot find any useful information or diagrams on how the OEM sockets are wired.The next problem is since I only have low beam lights, I have NO idea if the dimmer lever on the steering column even works. I have been working on this for the past week and am at wits end as how to rebuild the socket and have everything work properly. I would like to get this figured out ASAP so I can order the harness, sockets and lights so I don’t get pulled over for having an out light…

If anyone can crudely illustrate or point me in the direction of a simple diagram of how the OEM headlight sockets are wired I would VERY much appreciate it because I am basically at a loss at this point.

 

find a junkyard with a pre 96 and steal the headlight harness from it, it takes about 3 minutes to remove, and plugs in to the body harness under the air cleaner box, then you can plug in and install the headlight of your choice. Ebay also has them quite often. Get rid of the cobbled up wiring mess, and start anew.

 

Here's what I did on my 79 Camaro. Similar but, different.

There should be two wires from the headlight switch you are looking for. One for high beam, one for low beam. Might be a third wire coming in with the ground, don't remember if that wire went to the switch or a chassis ground. Anyways, find the wire from the switch for high beam and run it to a relay. Find the wire from the switch for the low beam and run it to another relay. The switch wire will then trigger the relay. If you aint following me at this point, this article has the basics, especially the diagram showing the terminals to connect to. Then chop a headlight harness from a junker and wire it to the outlet side of the load side of the relays (low beam to low beam relay, high to high relay). Then wire the inlet for the load side to the battery.

Fixes your F-ed wiring and upgrades the headlight harness at the same time. You can pull the needed parts from any junker. Most every vehicle uses the same headlight harness. Any two relays will do the job. I like the GM stuff from the late 90s or so. GM cars have relays mounted to a metal strip w/ individual plugs. Look at the older Chevy trucks. Easy to retrofit to older cars.