No. All the power for the headlights come directly from the battery and the original wiring is just used as a relay trigger circuit, about 2 amps at most! I bought mine from All Star Truck Parts on Amazon for $21.95 USD. All the similar harnesses seem to be Chinese, just from different suppliers. This one has ceramic headlight plugs so I can switch to H4 halogen without worrying about melting them. The only concern I have is finding replacement relays if I ever need them, but substituting other ones shouldn't be hard.

5 pin or 6 pin relays?
6 pin are BW4136, available at your local parts store and junkyard.

IDK Cruiser. I wasn't too concerned about it at the time. They are clear plastic with a mounting lug on the side. All I know about Chinese electrics is I've bought 3 sets of cheap fog lights on Amazon and the H2 bulbs didn't even last more than 2 nights! I've replaced them with Hella and they've lasted over a year using them just about every night I drive! The set I have in there now, one Hella lost it's zenon charge and I replaced it with a Sylvania from NAPA. I know a lot of aftermarket parts are made in China and are pretty good, but not so with bulbs.

I've never had a relay fail. even Putco.

I hope I'm alright to tag on here but, I've just made and fitted my own harness which works great except for when on sidelights. When on, the relay controlling the dipped beam is chattering away as it has a low voltage intended to turn the headlight on in low power. Is there a way I can safely disable this feature by pulling a fuse etc without killing another systems power supply? Thanks

Dude the KFab Suspension wiring Harness is bulletproof in IMHO...I mean I paid 25 bucks shipped...watched the youtube video that literally had my cherokee in it, and then installed some LED headlights. Whole system is night and day. I could not even see the road with the old lighting. This is like sunshine. Plus I love how I am not straining the old wiring through the switch anymore. Just get the pre made harness if you read this, it is so much easier than making your own, especially if you have no time to do anything(cant wait for the holidays to pass so I can work on my Jeep again) ugh so tired

In my instance, bought or build would be the same unless the pre-built uses less tolerant relays which do not attempt to turn on in the situation which my one is.

not quite sure I get what you are saying, but I do know if you are trying to run LED lights they may not draw enough juice to keep the relays pulled in.

It's running standard H4's. I think what I call side lights would be park(ing) lights in the diagrams. So when the side lights are turned on, I have a small 4W bulb on in my headlight unit. Along side this, both headlights turn on at I assume half power in a dim mode. My relay in the harness is taking that half power (6-7v) and is trying to turn on then off so it just buzzes or chatters. If required I could go out and get a video to demonstrate this. Leaving it like this will just kill my relay so I need to kill the input causing this issue.

Ah.
Yes the harness was not designed for that setup, I am guessing it has a relay with a 12v coil. So sounds like you need to disable the dim mode, or ditch the harness for one that can accommodate it with a 6v relay perhaps?

Just to follow up, on a RHD 95XJ, fuse 20 inder the dash soley powers part of the dimming relay. Pulling this fuse disables the dimming and the relay chattering.

It got warm enough here in Seattle to work on cars again, so I'm back at it. The replacement harness I got from the seller was fine. I put it in yesterday, along with the new headlights Cruiser recommends, everything's working as promised. Have not driven after dark yet, but the lights do seem brighter in daylight. I looked at this video for instructions. I found it easier to remove the battery, rather than feed the cables next to it like the guy does in the video.