For those who may be interested, a quick update as to my progress in sorting the above problem....

Same problem as all the other threads of similar titles i.e. ABS light on constantly, Traction and Stability on most of the time constant - occasionally only lighting up when moving off. Very occasionally all 3 lights will be off on start up until a few hundred yards have been travelled, then they light up again.....

Anyway, cleaned all 4 sensors - still happening but more frequent occurences of the Traction/Stability lights being off briefly after moving off.

Tried the resistance checks at the ABS module plug today as per the guide that is frequently mentioned....couldn't get ANY readings at all - thinking my DVM batteries are low.

Anyway, bit the bullet and pulled the ABS module out (it is really quite easy, only took about 15 mins of fiddling), opened it up and re-soldered the 2 power pins inside. They looked ok to be honest, but seeing as I had opened it up I thought it wouldn't hurt to do them anyway....

So, refitted the module - all lights on.

Turned ignition off and on - ABS on only.

Pulled away, Traction and Stability came on again.

Drove a few hundred yards, pulled in and switched ignition off/on again.

No lights!

Drove a couple of hundred yards, came to a junction and braked - I could feel the brake pedal 'bouncing' as the ABS did 'something'....pedal felt quite soft at this point.

Lights came on.

Drove further, pulled in and switched ignition off/on - lights all on.

Drove further, pulled in and ignition off/on. No lights - pulled away and all lights came on after a couple of hundred yards as I braked again (I could feel the ABS doing 'something' through the pedal again.

Light on constantly from that point....came home.

So....

Something in the system is working, and something isn't. Feels like the ABS was bleeding itself and gave up after a while.....not sure how long it has been faulty so maybe it's a bit lazy?

Anyway, I will carry out a full continuity and resistance check on all 4 wheel sensors and circuits tomorrow - when it's light again.

 

i have had so many ABS issues with my cars in the past that it sure was godsend for service stations and manufacturers that every car now must have it.
Good luck trying to find the problem!

 

The resistance at the connector is usually in the range 1.1- 1.3 megohm.

 

Hi Rich
Have you checked the fluid level in the brake reservior tank?

We are getting the abs light warning, Trac and Stability fault messages coming on a lot of times after driving maybe a mile.

I found a forum thread by member WaterDragon
https://www.jaguarforums.com/forum/x...odd-way-78792/

He mentions that he fixed the issue by lowering the brake fluid level just a little bit.

Worked for me (our brake fluid was almost to the very top of the tank).

Jim Lombardi

 

Jim, funny you should mention that - I just read that thread, and yes my fluid is very full (checked to see if it was empty today and thought it looked a but much....almost full to the brim)

I will decant some tomorrow and report back!

Cheers,

Rich.

 

I have an intermittant Trac,ABS error. Thanks for the info in this thread, will report back on what i find

 

Quick update:

Reduced brake fluid level - no change.

Checked all 4 sensor resistance figures - OK.

Removed module again and rechecked solder joints - OK.

Went for a drive - no change.

Did a hard reset - no change.

Checked all fuses (again) - OK.

Did some voltage checks, getting 12 volts to power side of pump fuse. However no voltage measurement at pump plug - then again I wouldn't expect to see one as the pump shouldn't run ordinarily on start up (I assume).

Ran 12 volts to the pump - it runs. Doesn't sound that fast but not sure what speed it is supposed to run at when normal anyway...

Resistance at pump leads - DVM reads 0.3 at 200 ohm setting (minimum setting on my DVM) - which 'I think' means 60 ohms, which might be a little high.....then again it might mean 0.3 ohms which is a bit low....think i read that it should be between 9 and 21 ohms on here somewhere...

So, I can only assume that the module is faulty somewhere (backed up by the fact that the ABS ran for a very short while yesterday as reported in previous post) and it cannot be the pump solder joints....

I have ordered a replacement module/pump assembly from the same breaker I got the diff from - advert says it was serviceable on removal from car and I have no reason to doubt that....

Will keep you informed of progress, expect module to be here by Wednesday....if that doesn't fix it then I am stumped. I know that i should have had the codes read by now - might pop down to the Jaguar dealer to see if they can give it a quick flash for me....

Cheers,

Rich.

 

When I bought my XK8 I checked it with AutoEnginuity and had two ABS problems. The pump circuit and left front wheel sensor. Swapping the sensor and cable with RF still gave the LF code, and the resistance readings were all the same.
I sent the module out for repair and both codes went away, so replacing yours is probably a good choice, assuming it's not much more expensive than a repair, which was on $55 on this side of the pond.

 

I think it's my last option - managed to get one for £50 delivered ($75?) so not too bad I think.....

 

Did you check the brake lights? I get the ABS, Traction & Stability message and the ABS light, when I turn on the rear fog lights.

 

Hi
If you are having any problems with the cruise control, then the problem might be the brake switch that is mounted with a bracket on the brake pedal.

Use this weblink to a thread and post on this issue - look at post# 8 (has a tsb in it):

https://www.jaguarforums.com/forum/x...n-light-76654/

Jim Lombardi

 

As it happens, I have had a brake light out for 3 days, your post prompted me into having a quick look....

Changed the offending bulb - brake lights now good, but rear sidelights wouldn't work!!!

After a bit of gaffing around whichat one point had the front sidelights refusing to work with the new bulb in the rear, the lights eventually decided to work correctly....very confused as to that event, that circuit is simple, right?

Anyway, disconnected battery - went for a run and low engine power still there (but still no engine light on dashboard) - starting to wonder if the ABS module is speaking to the Engine ECU to tell it to reduce power due to the ABS fault? In which case there wouldn't be an engine performance warning light because the engine ECU 'knows' it is performing correctly?

Confused.....need that replacement ABS module, at which point I hope all my troubles will disappear.

Jim, I haven't tried the cruise control yet - might give it a shot tomorrow...

 

Hi
When you mentined low engine power, did you mean "Limp Home Mode", any other messages such as "RESTRICTED PERFORMANCE".

The Jaguar XJ Drivers Handbook has this information on Limp Home Mode:



Jim Lombardi

 

Jim,

It appears to drive correctly through all gears, even revving correctly - just has greatly reduced power....even kickdown works but it feels like half power. It's totally driveable, but the Starship Enterprise performance is gone....

No warning signals or messages regards performance at all....still just the ABS/Traction/Stability warnings?

 

Hallo all, quick update....

Replacement ABS pump/module arrived today.

Fitted it and then bled brakes just in case.

ABS light still on, Traction and stability once moving.

Disconnect battery, hard reset.

Went for a very short run, stopping car and cycling ignition.

ABS went out once, brake pedal thumping when depressed as if the system was bleeding itself.

Then no lights - DSC light occasionally on pulling off.

Lights all out - quick run around block - happy days.

Pulled over, cycled ignition - ABS back on. Traction and Stability once moving....

Confused....

Came home - have disconnected battery again to see what that does....

Obviously the system works when it wants - next step to go to dealer to get codes read I guess...

 

I feel your pain!
At this point, I would give a good once over to the power distribution and grounding. I assume you know of the bulkhead power terminals . With the engine running and lights on, check for voltage between the ABS ground and the engine. Check from the battery terminal to the ABS 12 volt supply and so on, lookinf for anywhere where ther is more than about .5 volt difference. Low voltage has been reported to affect the ABS several times in the past.
And... The time has past to go ahead and get the codes for the ABS scanned.

 

Not aware of the bulkhead power terminal thing...I will do a search...

 

You do realize that there are probably DTCs in the module that will help you diagnose.

bob gauff

 

Check for a short along the ABS sensors wiring.

It faults back to the ABS sensors, because if you start the car, no ABS warnings. Once you start moving, the warning comes on. True sign of sensor related.

If it was the module, the lights would come on as soon as the car finishes it diagnostic check.

Take off the brake rotors and examine/clean the teeth on the hub rings.

Makes sure the ABS sensors are working.

 

Hello,

I saw a post somewhere that suggested removing the wheel sensors and cleaning them. Tried it and it resolved the ABS light issue on my car. One was covered with dirt / dried mud. Cheap fix!
Best, Dave