Group.
I am new here, and am humbled by the wealth of info and ideas here. I have read lots of posts about ABS/Traction Control issues. My Jag is a 01 xj8 with 104k miles. My issue is weird. I almost always get the warning light when I start the car. About 1/3 of the time, the light disappears when I drive past 5 or 10 mph. The rest of the time, it stays on. I have found that the warning does NOT come on as often when it is cold outside, and almost always on when HOT outside. I've replaced both front sensors, checked the brake fluid (full). My battery cranks fine, and the brakes have all been replaced. A repair-place once pulled (found out later) the vacuum line from on or near the break fluid tank, and the frequency of error seemed to go UP following that.
I've blabbed to long. Sorry. Any insight from you smart-about-Jag folks?
Thanks.

 

There is alot of talk lately about ABS modules having a internal wiring break issue, that when warm, expands and causes the fault. I cannot say it has 100% validity, but the module, when all else has been tested, replaced...and still exists, is the next piece to look at. There are a few companies nationwide that rebuilds these modules if you choose to start looking.

Anyway, look around, I don't know, but there may be more threads regarding ABS modules in the XJ/S/XK sections. Often these modules are used across platforms and you will see similar symptoms from them.

 

Thanks for the heads up. Looking around, it appears my best best is to have the module rebuilt. Some places don't seem to charge too much. Can you share where I'll find the module under the hood (bonnet) of the XJ8? I assume it is something I can get out.... yes?

 

I have also an strange ABS/Traction control message, not the same as above, may be similar:

Goes like this:
1) I put in the key, turn it to the position when all the lights on the instr. pack light up, I wait until they are turned off again. So far so good.
2) now I start the engine and for few seconds a message "Trac not available" appears and the ABS light is on. (the message could be slightly different, don't remember it exactly)
3) after roughly two seconds the message disappears, the ABS light goes off.
NOTE: I tried it out, ABS and traction control woks fine.

Thanks for any help.

 

Your module probably has a broken motor circuit plug. I CAN confirm that is a common fault as I have repaired two of them (out of three cars!). Find the module under the valve for the ABS, which can be identified by the six brake lines connecting to it. There is a lot in the archives for step by step. In your case, I would not worry about it until it gets where it will not clear. Good Luck.

 

Here is a link to a related discussion on the ABS/TC issue: https://www.jaguarforums.com/forum/s...ead.php?t=3853

There is another with excellent pictures on opening and re soldering the circuit board connector but I cannot instantly find it. Perhaps someone can pull up that link. That is about what a rebuild consists of.

 

This is what I have but you may be required to get a sign on http://forums.jag-lovers.org/av.php?1216605k87 I also have a place that you can get them rebuilt http://www.modulemaster.com/en/index.php I also have other links on my page.

Hope this helps!

 

This might be a nice addition

 

before you go spending a ton of money on this...i had the same problem with my 2002 vanden plas. I had to get my control arm bushings replaced and one ball joint. While doing this they cleaned my abs sensors and i havent had the codes pop up since. This was a year ago..id suggest getting your sensors cleaned first as it could be a very cheap fix..

 

my bad didnt see that you already replaced the sensors! good luck though

 

I did the repair listed on Jag Lovers to the ABS module on my Volvo T5 which would throw an intermittent ABS light (it's the same or almost identical module). The large power connector pins are the ones which cause the problem - they are harder to solder when made than the smaller component joints and that plus the current draw seems to cause one or more of the joints to fail in service. A couple of mine were so loose I wondered how they ever mad any connection at all! For the sake of a few hours work and a bit of soldering plus some RTV compound I save quite a few hundred dollars and it has been perfect ever since.

Don't start this unless you have the right star drivers and can make a really good soldered joint. Don't use an underpowered soldering iron. I have a temperature controlled 45 watt job I use for general electronics and it wasn't enough. Eventually I used a gas-powered iron with catalytic tips (roughly equivalent to a 100 watt iron) and it was perfect. I wouldn't hesitate to do it again if I had a failed unit on one of the Jags.

Jim

 

Anyone know If this can be done without removing the brake lines?

 

If you're referring to my post, you don't touch the brake lines. The ABS body pulls free of the metal body carrying the abs valve solenoids and brake lines. You are only removing the circuitry and the solenoid actuator coils.

Jim

 

Yeah should have been more specific I was referring to the removal of the abs module. So the module can be removed without removing the break lines... that's good news the XK8 guys made it sound like for their set up that lines have to be taken off. Do the lines require some bending to get them out of the way?

Picked up my star sockets from harbor freight today. Also have an autoenginuity scanner on order so I can double verify that its a pump issue and not a wheel speed sensor issue.

 

Yeah, I see what they mean. The brake lines bend over and around the module. You need a straight pull of a couple of inches to get the ABS module off and there may not be clearance. You'll have to experiment, I guess, or perhaps someone who has done it on an XJ8 could chime in to say whether judicious bending works or if it is a disconnect job?

Jim

 

I swapped out an ABS pump last week on an XJ, there's four nuts holding it to the chassis, easier to get to if you take the front bumper off first, and undo the overflow tank, then you can get at them, they're underneath. Once they're off, you release the lines (keeping them in their clips) from the chassis leg up to the front bulkhead. Then you can lift the pump assembly up enough to remove the module, put something underneath it to support while undoing the nuts. It's better than disconnecting the pump lines and the potential release of brake fluid all over the place. Hope that helps

 

Hmm I'm hopping that I won't have to pull the entire pump... hopefully just the control module in the plastic housing.

 

I have had the same Trac not Avail problem a few times. My mechanic said the sensor can get dirty (driving over a very dirty road). Usually shutting the car off and restarting it solves the problem. yesterday it happened again, I switched to Manual shifting while driving and it went away never to come back after switching back to automatic. I guess some of these problems are temporary, but the codes and warnings don't disappear unless the car is shut down and restarted.

Just some input from some a newbie

 

4 nuts to release entire pump assembly plus unclipping brake lines from various hold down and movement of some relays resulted in me being able to remove the module (controller - plastic box) with out unhooking the brake lines. I did have to make some minor bends to the brake lines, but nothing unreasonable.

Avoiding not bleeding is really going to speed this job up. In about 3 hrs I got the module out, opened it, re-soldered and now have it glued back together drying in a vice.

Additionally I used one of these new fangeled "multi-tools" that you may have seen on TV to get the box open (they have them at Harbor Freight). It vibrates a cutting blade and cut into the plastic quite well. I would recomend the variable speed model and a patient slow hand for this job.... I think it is probably easier than an exacto and hacksaw.

 

Hope to hear how that turns out for you - I am about to go boldly...