XKR ABS Light on.

[carl.smith998]

Hi Guys.
First time Posting.
I have a 2002 XKR 4.2 Convertible, I purchased the car over a year ago and only wanted to use it in the summer months, when I purchased the car, the previous owner told me that there were a couple of faults that were caused by a weak battery, I.e. door windows not set in position. I have sorted that, also he said that the DSC light sometimes comes on but doesn't affect the driving, I drove the car back from Sheffield, approximately 140 miles, the DSC light did come on after 40 or so miles, I pulled over, turned the ignition off, then back on, and the fault did not re-appear, I have only used the car 3 times in the last year, other than that she sits in a heated garage, I replaced the Battery for a new one and because I don't use the car often, I also bought a battery optimiser which is always connected. I took her out a few weeks ago for the MOT, unfortunately after a mile or two the DSC light came on? got the car home and connected my ECU Reader in and cleared the codes, I did not make a note at this time because I was in a hurry, got to the MOT Station and the light was still not illuminated, unfortunately the car failed the MOT because the ABS light came on? I had a guy come out to read the codes, he told me that it was the steering position sensor and that this had to be fitted by Jaguar as they need to set it up, I now know this not to be true, anyway Jaguar fitted the new sensor but told me that there was still an ABS light on and I could re-book an appointment, I did not have time for this as the MOT ran out that day, I called the mobile technician again and he told me that it was showing the front off-side wheel speed sensor? I decided to replace all four sensors, started the car, light still there, used my code reader and cleared the faults, started the car and the ABS light is back on, tested the cables from the Module to the sensors, all seemed fine but I replaced the off side cable, still the same fault, took the car to a local garage for testing, he ran a live feed test and it showed the nearside sensor? had him clean all the reluctor rings and re-test, now showing both front sensors? grr. he advised that it would likely be the ABS Module at fault, I sent the module away for testing with a reputable company that specialise in ABS modules and they have come back with No Fault Found, where to go next? I understand that there is an earth loom and earth points on the car that could be the cause?
Just an additional note, the sensors I replaced for were not original Jaguar sensors but the fault is only on the front?
apologies' for long post but a lot has happened.
can anyone please advise?

[andypryce]

Sounds like you have replaced almost everything except the module, although the company said it was not faulty I would still try swapping it for a known good one, if you can, and see if this cures the problem. Yes, earthing could also be an issue, but that should be fairly easy to spot, I am sure someone here can post up a diagram of all the earthing points. Good luck!

[Astromorg]

I certainly don't have an instant answer to your problem, but I will make a couple of points that might help you make some progress. First, you give the details of your car as a 2002 XKR 4.2. That is true no doubt, but being a 4.2, I suggest that it's a 2003 Model Year, Jaguar's MYs beginning well in advance of New Year's Day. This is important to note when ordering any spares and in particular the ABS/DSC system that was a new design for MY2003, so I'm wondering if the new wheel sensors you obtained are the right ones because the early and late ones are not interchangeable. Early sensors were of the Passive type, post MY2003 they are the Active type.

The ABS/DSC module is not often the cause of trouble in the 2003 version but it has its own codes that should help if it is at fault.

Common causes of DSC fault messages are
Dirty reluctor wheels. Done
Broken front sensor harnesses through flexing. Usually an intermittent fault. (One done, one to go?)
Incorrect sensor-to reluctor clearance. Is the sensor fully inserted ? (No figure for the clearance published.)
Do the new sensor dimensions match the originals to ensure correct clearance?

Do you know if the scanner that came up with the codes was a fully Jaguar enabled system? There are a total of 37 separate DSC faults listed by Jaguar and you can't afford to be maybe missing the vital one!

Further to Andy's post about ground points, the only significant one for this system is in the nearside bulkhead box (Opposite to the one with the brake servo etc) where the two Black ground wires from the ABS/DSC Module are terminated.

[carl.smith998]

Hi Guys.

I have never posted on forums before because I think that you can get bogged down with all sorts of advice, but I have to be honest I'm impressed with the suggestions so thank you.

Really interesting information and obviously your very knowledgeable, firstly thanks Andypryce, I was considering replacing the module and maybe further down the line if I can't get it sorted then I will, the testing centre tested the unit with their own sensor mock set up, testing with vibration and heat but no faults found, they said they were getting balanced readings from all 4 but we'll see.

Astomorg, again Interesting information, you are correct, my car is a 2003, sorry typo, it is very possible that the sensors supplied are for the earlier cars, I will certainly check this when I'm in the garage Saturday, but in the meantime, I will order genuine Jaguar sensors, (lesson Learnt) I will also check the earth points mentioned, regarding the sensor cables, I did do a continuity test on the front off side and all was good but I replaced it anyway, I will also order a new cable for the nearside, "in for a penny"
Big thanks Guys.
I'll report back over the weekend.

[andypryce]

For the sensors try either eurojags or one of the other suppliers, eg David manners or sng barratt. I find eurojags in particular really good for parts, if you ring them they always are very knowledgeable. Their website is not great though, better to ring them. To get correct parts they will need your VIN though, obviously.

[aaj]

Carl
I had various ABS issues on my MY2002 XK8, faulty front drop leads mainly & eventually the electronic part of the ABS Unit failed. The microswitch inside the Break Pedal Switch is known to fail causing various issues including warning messages regarding the ABS. Switching off the Cruise Control at the switch on the Center Console disconnects this element of the ABS System and therefore the error messages stop (fault codes need clearing). I don't know if the MY2003 on Electronics would produce the same effects, perhaps Astromorg can advise
Good luck
AllanJ

[Astromorg]

With the introduction of the updated system for MY2003, the Cruise Control On/Off switch was deleted! Cruise control is always available and operated entirely by the switches on the steering wheel.
Any fault in the ABS/DSC system that lights the amber warning light automatically disables cruise control

[carl.smith998]

Hi Guys.
Firstly, thanks for all of your replies and advice, I'm happy to say that the ABS issue has now been resolved
Yesterday I had an old friend, who is an auto electrician visit and to take a look at my XKR, he went through all of the tests and after about an hour, found the issue, as I mentioned before, the fault code readers identified an issue with the front off-side wheel speed sensor problem, I therefore replaced four of the sensors due to their age, I also replaced the front off-side link cable (Genuine Jag Part) partly because I was made aware that these often fail, that was my first mistake but unknowingly, after carrying out all of his tests and with the reader still saying that the issue was with the front off-side sensor, he examined the NEW cable and found that the wiring was incorrect? I'll explain, on the top plug the x 2 cores fitted did not correspond to the lower (sensor side) plug, basically, when the lead was manufactured the two wires were fitted to the wrong side of the plug, I.e. (twisted) he removed the cores from the lower plug, swapped them around and re-inserted, plugged back into the sensor and hey presto, ABS light went out and all faults cleared, happy days, It's really annoying though that this has cost me in the region of £800 and due to a faulty (New Genuine cable) If I had just replaced the sensor then that would have sorted out the issue, but I thought it best due to age that I do a proper job.
Hope this helps anyone with similar issues, but It's good information when buying these link cables.
Thanks to you all.

[ptjs1]

Carl,

Good to hear that you've got it sorted eventually!

If I were you, I would definitely contact Jaguar Classic Parts to complain about the faulty cable that you bought from them. Firstly, to try and get some compensation for the part and labour that it's cost you. And secondly because maybe all of that batch of cables are incorrectly manufactured and they need to withdraw them and also contact any other customers who have purchased such a cable.

Good luck

Paul