I think that may happen even if the module is OK, because when faced with a barrage of error signals from the e-diff, it probably goes into the equivalent of limp-home mode. Up to you if you want to spend the cash, but if you get the ADCM replaced at the same time as the loom and actuator, you'll never know what the actual problem was. Golden Rule of Troubleshooting: never change more than one variable at a time! Well, unless it's an emergency...

 

I agree I won't have them change it at the same time as much as I don't have the time to keep going to the dealer etc. My concern is that the ride can be bouncy randomly even when theres no warning light but of course that doesn't mean its not recording a fault.
I've opened a complaint with Jaguar North America, more about bushings and doors not latching. The E diff fault although annoying is a just fault and that will happen with the best of systems, the rubber boots, peeling insulation, door latch these are more concerning as they speak to very poor design or quality control and speak to if I want to keep the car. Unfortunately its reminding me of owning new Land Rovers in the 90's nice trucks but Lada (before VW) could have taught them about build quality

 

Another update. The XKR is still in the dealer went in on Monday the factory apparently incorrectly labelled the harness and shipped the wrong one so now its apart waiting on the correct part to arrive from the UK current estimate Tuesday or Wednesday.
So I've owned her for nearly 2 months and she's been in the shop roughly 3 weeks

 

andy , what kind of history did you get with this car. It seems there has been a unusual amount of problems for such a short ownership. What kind of mileage do you have on it. Is it a CPO car

 

The car had 23,500 on when purchased, currently approx 25,000 the car was one owner in Florida, full service history reported on carfax Palm Beach Motors, Florida.
Jaguar confirms the service history. The only issue prior to my ownership was a faulty tire pressure sensor replaced at 13,169 miles. Serviced by dealer every 6 months almost to the day. It was traded into the Ferrari dealer in Palm Beach who kept it for 2 months before selling it through auction to the dealer in Chicago from whom I purchased it.

 

Unbelievable

 

There's more to this story. Sometime is not making sense. The OP bought the car knowing it had problems and never returned it to the used car dealer. Something is missing. There was a thread started by the OP sometime ago when he bought the car and all of these problems appeared. Any reasonable person would have returned the car to the selling used car dealer. This car must have been abused or involved in a flood which are not being disclosed for all of these problems to happen. Is the OP trolling the forum. This is not making sense.

 

Its interesting the original owner purchased new in 2011 and serviced it every 6 months are Jag palm beach. Jaguar have confirmed the service record. It was purchased by the Ferrari, Maserati Palm Beach who kept it for 2 month before selling it through auction to dealer I purchased from in Chicago.
I've talked to the Jag dealer here in GR which are working on it and asked if they have any impression that there is something strange in its history and they say no, it looks like a un molested genuine car to them. I've talked to Jaguar north america, there convinced there car is straight.
Its good to hear that people here are surprised by the issues because that gives me confidence that its not Jaguar poor build quality in general. I have a emotional attachment to Jaguar having worked for TWR on the LeMans cars of the early 90's on the XJR15 and I worked with Ian Callum on the XJ220. I'm English (living in the states) and would love to be able to tell people that Jaguar's are great cars.
Unfortunately I am a picky owner and notice things that a lot of people don't. I have a new Jag XF as a loaner, earlier this week I used it is a example of poor craftsmanship to a customer management for interior trim fitment. Looking around a F type coupe at the dealer the drivers window was topping short a whole 1/8th when compared with the right hand window.
With this in mind I'd say everything I've seem with my XK is in line with current Jaguar build quality.

 

I'm guessing you never owned a TVR, then

 

No never a TVR, a Triumph yes

 

A friend of mine has one. I think it's a 70's MY with a 289 Ford with a 4BBL. Runs like a raped ape but the wiring looks like a squirrels nest. Lot of little things but it is quick. I sat in it once and didn't think I could get out , lol. He mentioned he got it as a steal but as I mentioned it needs some good amount of rewiring. He's working on it wire by wire but drives it occasionally.

 

TVRs are notorious over here - if you get a good one, it's a lot of fun, but there are plenty of garage queens, and I've seen quite a few on the motorway shoulder and low-loaders after they expired.

 

Quick update the cars still in dealer 2 weeks on Monday correct part still not delivered to dealer after the first delivery was the wrong part with the right part number !
Jaguar North America still playing dumb either unable or un willing to answer specific questions about things like torn rubber boots. All they want to do is call the dealer to ensure its given priority smfh.

 

Have you thought about low voltage problems. It seems when these cars sit for a while they start throwing all sorts of weird unrelated codes. Perhaps it need a new battery or just put on a battery monitor for a while.

 

There's no signs of low voltage other than the original multiple codes which was corrected under recall for a software upgrade, not voltage related but obviously a known issue to Jaguar.
Other than the time it sits at the dealer the car doesn't sit for long its intended to my my daily driver. when its available didn't buy it as a toy
Seriously, Jaguar and the dealer are convinced its the wiring harness and possible the actuator motor for the clutch pack on the diff. Its the wiring harness which is taking time to arrive 2nd attempt at the right part. my thoughts are it may the control module or temp sensor in the diff. Its seems to be related to low temps -10f and lower, obviously this could be thought of voltage related but there are no other indications, no other odd behavior at start up. The only related symptoms are intermittent poor ride quality. I think the dealer thinks this is either my imagination or because the Diff fault is causing issues with the control module which also controls the dampers. I have asked the dealer for a cost to replace the control unit on my dime lol as I'm getting impatient.

 

I am betting it is a battery low-voltage issue. No XK can have this many problems...and you would be amazed at what less-than-optimal voltage can do: random symptoms in every and any one one of the electronic systems, and not consistent in any one of them. It can be in the seats, touch screen, windows, door locks, roof movement and latching, warning lights galore, etc., etc.,
When you get the car back from the dealer after weeks of investigation, reflashings, updates, and possibly new parts, the battery will have discharged even further. Expect more "problems".
Or, you can charge the battery and then fit a battery maintainer such as the CTEK. The fact that Jaguar sells this under its own label (as does Audi, Mercedes, BMW...) should suggest something. See the photo of my happy and absolutely trouble-free XK with the CTEK unit plugged in.
In any case, please DO tell us the outcome of this investigation.

 

I think Andy's well beyond that point now - even the dealer thinks is a real fault, not a voltage gremlin. The only question is: what is the root cause? Module, actuator, sensor or the wiring in between?

The problem with the OBDII codes is that they're reported by the 'intelligent' part of the system, i.e. the module. So the module says "Invalid signal from component x" - does that mean component x is actually broken, or is the module faulty & mis-reading it, or is the signal getting scrambled by bad wiring?

 

Yep I agree with you here. OBDII system was/is a good guide to pin pointing a problem but what it has done has changed diagnosticians to parts re-placers. It will be interesting to see how this plays out. In the days of old all the tech had was his experience and a multi-meter. With the introduction of all of the on-board processors it would be impossible to live without it. By the way I think it is a great tool and use it as a start in finding a problem.

 

I've been reading posts on here for a while now and this seems to be exactly what a low battery does. Several unrelated problems that they can't find. Then changing parts with no solution. Try changing the battery and putting it on a battery monitor if they can't fix it this time. If nothing else you can eliminate the question and at some point you're going to need a monitor anyways.

 

I appreciate the input on the battery / Voltage and I have mentioned it to the dealer they remained convinced the issue is either the harness ( the delay is shipping of the replacement, that I'm afraid ranks as shear incompetence on the part of Jaguar) and or the actuator. Jaguar are replacing both.
In fact once the initial CEL software upgrade was done (first dealer visit) the errors have been consistent (E-Diff Fault) these have been the last 3 and current visit. My other concerns about the car are physical ie torn boots.