Below is an image of a patch harness that is found front left of the car between the main harness and the front bumper harness (RHD vehicle), I have drawn a total blank trying to obtain a replacement.




The harness had been previously repaired - pretty badly - and it was an absolute bear to remove as the spring clamp was broken so could not been removed without some brutality - the parts below are what I cut out, the image above is my repaired version but to be honest I'd prefer to replace if I can.

 

Ben, you may want to see if your local dealership can help you with obtaining a harness. Atleast with that, you can get a part number. Not sure if a site like JagParts.com may be able to get you the info you need.

Of interest, I see some of the lines are twisted together. Those are most likely data lines and that twisting in the wires is important. So, if you do some repairs, make sure to add that twisting back in. If at all possible, twist it the same number of turns per inch/CM. The number of twists over a given distance sets up the frequency that it will block. If you open up normal CAT5 cable, you will notice that the wires are twisted together and 1 pair is twisted at 2 turns per inch, another at 3 turns per inch, and a third at 4 turns. Forget what the last one is twisted at.

If you do have to keep this repaired harness in your car, I would recommend finding some Raychem heat shrink and put it over the repairs. This will help keep the water out of the repaired places and give you something that will be as good as factory. If you need some guidance on using the Raychem, let me know. If you think you have applied enough heat, apply a little more. Really hard to hurt the Raychem and you need to make sure that the glue on the inside of the tubing gets warmed up so it will seal the tubing to the wiring (noted by a little glue "donut" forming at the end of the tubing).

 

I took it to my local dealer and even they cannot find it, there are only three harness parts listed under the hood of a Jaguar XJ. The dealer believes that it must be included with one of those parts, in fact item 2 on the image below since I have a brand new item 1 in my hand. If that is the case a repair or finding a secondhand is the only option since item 2 is listed at £1800 + tax for a car with active headlights - not a snowballs chance in hell I'm paying that.

 

Any chance of finding a used one off EBay?
You would need to guide the seller to remove the part you need but is that harness difficult to remove from the car?

Here is a place in Germany that seems to sell intact wiring harness's?
Take a look;
Jaguar Wiring Harness

Too bad you don't have a part number to look for?
Here is an engine compartment harness but I can't tell if what you need is included in that or not?
XJ Engine Compartment Harness
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You don't really know this harness is there until you remove either the wheel arch liner or start to pull the bumper. I have found the connectors in China of all places and ordered some, worst case I will totally remake using the old as a pattern.

I do agree with Thermo that 4 of the pairs in this harness are communication cables as they are twisted so any patching must not only maintain twist but also length, not sure how sensitive the control modules are to timing but if they're very critical then introducing unnecessary connectors is pretty stupid.

I have approached at least 8 (would have to dig through the email) and my feeling is that most vehicle dismantlers are too lazy to even go and look - before all the health and safety bull***t in Europe we could go walk around and look ourselves - I believe they still can in the USA.

Easy to remove - sure it is as it is only a patch cable it isn't part of the main under bonnet/hood harness or the bumper harness but simply connects one to the other. I've seen a number of listings for a full under bonnet/hood harness but have failed to discern this particular piece, I've sent emails to every one I've found.

I have repaired mine as best I can respecting the twisting, I have also used glue lined shrink sleeve but to be honest I would rather have an un molested part in this location.


These are thje connectors if anyone is interested >> 16 Pin Automotive Waterproof Connector Square Connector with Terminal 7222-7564-40, DJ7161Y-2-11/21





I ordered from AliExpress which is where I tracked them down, I don't know if the reference above is the actual connector designation that everyone understands or not - I've not found it elsewhere

 

You are way ahead of me here so good job!
What a hard wire harness to find.

Yes we also were able to roam the junkyards at will in the past but between all the parts theft and safety/insurance garbage. Most yards don't allow anyone in anymore. Of course we do have a lot of Pick and Pull yards and those are pretty much 100% DIY parts pulling. Boy what a mess those cars are too! People just smash everything to pieces getting their parts. At least where they don't let you into the yard the yard guys damage less stuff.

For me the worse change is that scrap is worth so much that the cars don't stay in the yard very long because they want to scrap them and get more in. So parts rapidly disappear as the cars age.
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