ABS warning light continually on.

[BillDag]

Jaguar XJR 350 2004.
Left home the other day to go up to London within a couple of miles ABS warning light comes on and no traction control light plus the warning messages in the information window.
As I was only a few hundred yards away from my local independent Jaguar specialists in Newton Abbot (S & P Auto Services) I decided to put the car in to see if they could give it a quick check.
They confirmed a fault in the ABS system and if I had to drive the car be very careful.
I have a copy of Jaguars SDD diagnostics so the first opportunity on my return home I ran the program.
I received the following report/recommendations.

DTC Help for ABS C1235 100%
Description
Rear right wheel speed signal comparison fault.
Detail System: Dynamic stability control system.
Control module: Dynamic stability control module.
System malfunction indicator lamp:
System malfunction indicator lamp (if fitted) is not activated.
Possible causes: Rear right wheel speed sensor failure.

Part of the recommendations was to first check out the wiring between the ABS multi pin connector and the right rear wheel speed sensor connector. The wiring continuity checked out ok, and test the ground proved clear.
So must be the wheel speed sensor, check that out measured 725 ohms in one direction which led me to believe that wasn't much wrong with it decided to replace it anyway. While waiting for its arrival I checked out the left-hand rear wheels speed sensor and its associated wiring all proved ok.
I fitted the new wheel speed sensor cleared the fault codes and within driving the car 100 yards warning lights and messages reappeared. Got back home with the car and carried out all the above checks again. Although I could not see any problems with the reluctor rings and the air gap between the sensor and the ring was uniform I decided to give them a good wire brush and scrape out all the little holes. Cleared fault codes once more and drove the car once again warning lights and messages reappeared within 100 yards. Rerun home and run the diagnostics, received the same report and recommendations as above.
So am I looking at a fault in the ABS module? I did hear somewhere of one of the soldered connections on the ABS module circuit board on XJ 308 cars giving problems.
Any information or advice gratefully received.
Bill Dag.

[J44EAG]

Try this idea, Bill. Similar symptoms.

https://www.google.co.uk/url?sa=t&rct=j ... GrC1hAOy9A

Mike

[BillDag]

Mike.
Thanks for pointing me to that post, but alas all my connectors are sound and dry.
Those catches for the rear seat are devil to find and operate. Although there was some good explanations on how to remove the seat is not until you get it out that you realise exactly what you were trying to do.
I took a photo of my car with the seat out and will try and post it once I have worked out how to do so.

I didn't think there would be much amiss with my wiring as when I checked it I got a reading of 0.4 ohms. Manual states up to 5 ohms is acceptable and both circuits are clear to earth.
I fear I'm lead back to the ABS module I know there are quite a few posts and information on dry joints regarding XJ308 series cars. In fact a friend of mine who bought my 308 had a similar problem he is familiar with electronics and repaired his is by re-soldering the power terminals to the pump and has been running quite happily for over a year and it's in daily use. I found a couple of companies that overhaul the ABS units around £250 to £350. It's not only cost if I was certain it is the ABS unit I send it away but added to that It will mean disturbing all the hydraulics, though I am not left with much else to look at.
So bought a cheap unit that supposed to be working off eBay. My reasoning is to examine it and maybe swap the electronic modules just to see if it clears the problem. Will keep you and the forum informed of progress.

Regards
Bill Dag.

[ptjs1]

Bill Dag,

Sorry to hear about the problem. IMO I still think there's more chance on an x350 of it being a sensor or a reluctor ring. You haven't mentioned if you've checked the ring for integrity, no dirt etc. If the ring is perfect and the sensor gap is ok, why don't you swap the two rear sensors and see if the problem moves to the other side?

Good luck

Paul

[BillDag]

Paul thanks for the reply.
Yes I checked the wiring 0.3 to 0.4 ohms from the multi pin connector of the ABS module to the WSS connector. Manual says 5 ohms or under, both circuits clear to earth.
Checked the wheel speed sensor 725 ohms in one direction , checked the other wheel speed sensor read the same. Purchase and fitted new wheel speed sensor checked that and it also read 725 ohms in one direction , problem still not resolved.
Checked and cleaned the reluctor rings all in order.
Have now received the used but guaranteed working ABS module.
I decided just to plug it in but not disturb the hydraulics of the unit in the car. Turned on the ignition did not start car, dashboard lit up as normal and after a few seconds all lights went out as normal yes the ABS warning light as well but not the DSC, maybe I need to run the car to clear this.
So it's looking more like the ABS module.
Although both units look identical their part members do differ. The unit purchased come from an S type R, they assured me it is suitable for my XJR350 looked at some other sites they offer units as suitable for either of the cars.
But there is still a difference in part members, and although I carried out a web search I cannot find anything to explain the differences.
The unit in my car has the following numbers.
DSC 4W93-2C219-BE. ATE part number which I understand is the important one relating to the electronics module is 10.0925-1009 .3.
The unit I purchased. DSC 2 W93-2C2 19-PC. ATE number 10.0925-1007.3.
My next move will be to swap over the electronic modules. Once electronic module is off the ABS unit on my car I will try to put a live supply to the ABS motor to check that runs. On this model of ABS unit the ABS motor connections are internal by way of a long plug from the back of the PC board, it passes through the aluminum body and connects to a socket in the motor. If the motor proves OK I will fit electronic module of the unit purchased.
I'll let you know what happens.
Bill.

[J44EAG]

It is well worth a try with the module, Bill.

Have you checked the ground points behind the headlights? 10mm nuts on studs with cables and ring terminals fitted. They can get in a mess. Similar issues on the ground cables in the boot but much less common.

Mike

[ptjs1]

Bill,

Don't worry about any ABS or DSC lights that stay on when the ignition is on, especially if they've been tripped previously. You can't conclude anything from that on an x308. You really need to drive the car at 20mph+ and see if they then go out and stay out as the sensors then see and correlate to the rotation of the rings.

Cheers

Paul

[stevencross671@btinternet.com]

Hi. Can any one tell me if the x350 2003 xj6 abs wiring cable is the same as the s type,? I know the sensor is the same but will the s type cabe fit my car because I am struggling to find a x350 one.
Thank you

[J44EAG]

Regret I can`t confirm similarity. It might be worth talking to Eurojag who break both models. Not much they don`t know about the types they "recycle" for good used spares. Remember to have the last six alpha/numerics of your VIN when you call them.

Mike K

[stevencross671@btinternet.com]

Thank you Mike. I will check out eurojag. Many thanks.

[mark.gill63599]

Hi i have a similar problem with my xkr 2004 convertible ABS light stays on had it checked by a local jaguar specialist .
He diagnosed the ABS module is at fault only problem i have is i can`t find anything other than a brand new one which i have been quoted at £1700 .
Unfortunately i can`t afford that amount and i am unable to find a replacement used or refurbished no one seems to have one is there an alternative as my mot is due in a few weeks .
The module number is 3w83-2c405-ac is there an alternative ?

[J44EAG]

In my experience, fitting a part with an alternative part number is unlikely to work. Replacing like with like with EXACTLY the same part number is the only way to go. Have your tried Eurojag or Auto Express or typed the part number into a search engine ie Google?

Mike

[PaulGover]

Some episode of Wheeler Dealers (sorry, don't remember which) took a duff control box of some sort to a group of electronic wizards (and don't remember who) and got it repaired for comparative peanuts. It would appear therefore there are some people skilled with soldering irons and modern controls who can sort these beasts out.

[naki]

2003 XJR 4.2.

I thought I would tag onto an existing thread, rather than start a new one.

I have a broken Reluctor ring on the OSR side. I made a failed attempt to repair it. I thought I had done a good job, welding it back together, but the fault code for missing tooth is showing now.
Anyhow, I bought a brand new ring to go on.

I have searched around for a how to guide for the job. But I haven’t found anything specific. I believe it’s the same for S-type too.
If anyone has seen a guide out there, it may be helpful.

[naki]

I was planning on doing the job today, until I realised I couldn’t find a 36mm socket for the big shaft nut. 34 and 38mm present of course.
I have ordered another so I have a bit more time to gather some ideas.

Ps- it’s taken me 2 years to get around to this job..,