Well I have been getting the dreaded ASC/TRAC unavailable with ABS light on more frequently. It would go weeks without showing but it now came on 3 time in the last 2 days, I thought it was time to find out what was happening.

The two listed frequent causes are:
#1. Dirt and magnetic bridging on the wheel sensors.
Removed each sensor and checked for continuity. While some gunk was evident, and each measured between 1000 Ohm and 1200 Ohm, I stll had the error.

#2. Pump motor connections in the ABS control module.
I hoped for #1, but as you can expect, it was not to be.

On reflection, I am quite certain that with the consistency of typical manufacturing processes, most all assemblies WILL fail with these dry weak solder joints.

Tools
8mm socket - Sensor removal
T25 Torx drive - ABS assembly removal
3/32 socket - ABS module removal

Soldering iron
Silcon gasket sealer or E6000 craft glue

Process
I elected to leave the brake lines in place - having read it 'can' be done.

Easier said than done, but it can be done

1. Identify the module you will remove and check out teh area.
2. Detach the relay monted near the module to increase clearance
3. Release clips retaining the brake lines to the chassis near the cylinder bank and the upper ones near the fender.
4. Pull up on the retaining lock of the ABS electrical connector
5. Remove the connector to the ABS pump (2 wire)
6. Use the T25, remove the 3 mounting bolts (5 min)
7. Use the 3/32 or suitable small TORX socket drive, lift the assembly and remove the 4 retaining bolts of the ABS assembly. (5 min)
8. Now, you will need to get about an 1" (25mm) of clearance to move the ABS module clear of the ABS valves.
   The module should be loose at this stage, just not able to clear due to the brake lines.
   If you need or want to bleed brakes, you could open the lines here and get the clearance to remove the ABS module.
9. You can use GENTLE bends and SOME force to open up the bends and to add some reverse bend to the straight sections of brake line.
   I know this sounds violent, and some force is required, after assembly and relocation, it still looks factory straight.
10. While pulling the lines, manoever the module out and away from the ABS pump assembly. (5 min)
11. At this point, you will need to remove the ABS Assembly cover.
    It seems the cover is glued in place, so it will either need to be cut free or the seal broken. I broke the seal around the edge as follows.
12. Place the Assembly in a vice and with a straight blade screw driver, lever down around the lid assembly to break the seal and ... eventually lever it off. This took the longest time. (15 min)
13. With the cover off, you will hope to see a poor connection to the 2 pin ABS pump. I was relieved that I saw a poor connection.
14. Resolder the connection and check for any other poor connections. I did not see any.
    In the case of electronics, my experiences are that 90% of the problems are either with a physical connection to the world due to vibration and dirt and user forces on buttons, or a high current connection. In this case the high current, temperature and vibration caused solder fatigue and weakness.
15. Depending on how you removed the cover, glue it back on.
    Some use silicone RTV type compounds but I loath these as the acetic acid curing can affect copper circuit traces if in contact.
    I used E6000 Solvent Sealant. It is water proof and flexible.
    Wait until the sealant has set before reassembly. (>1 hour)
16. Reassemble the ABS module back to the ABS assembly and reverse the assembly process.
17. Reattach the connectors and realign brake lines.

Ignition key on and check for no system errors and have a helper press the brake pedel while checking for no leaks.

Test drive and validate normal brake operation. You can check ABS operation carefully on a wet or dirt / gravel road.

I hope this process helps others with the error and wondering how to proceed or to give you confidence to proceed.
I am sure it saved me an expense that I can now otherwise use.

 

But was the operation a success? Is the patient all better now?

 

Yeah, that looks really good. Was it just those two connections to the ABS pump ? If so, it doesn't look too bad to fix.

 

Nice! Just what I need as I'm getting the same codes and probably need to get this done. Thanks for sharing!

 

I believe she is in full remission.
After having received multiple errors per day in the days previous, I have not seen any recurrence since. While it may be coincidental, I believe that the condition of the connection was pretty poor and a classic 'dry' joint causing intermittent connection.

 

Well, I did everything per instructions. Took it apart yesterday, soldered, and glued it overnight using black rtv. Put it in today and viola ! Works and no abs light and codes.

Few more tips:

1. If you lighttly heat up the case with a torch it softens the glue when you're taking it apart.

2. A head on one of my Torx screws stripped out and since space was cramped it was a pita go get at. Craftsmans power screw,bolt out saved the day. Well worth $25.

Also, some dielectric grease on the 2 pin, pump motor, connector will probably make things a bit better too as I think a poor oxidized connection at the connector heats up the thick pins and desolders the joint.

Anyway thanks to dsetter for a good writeup and pics.

 

The secret remove the windshield washer filler tube (1/4 twist an d viola.) remove the one bolt holding the cover plastic piece. Then you have a whole lot of room to remove bolts and unit. Five minute deal really!!!!!!!!!!!!!!!!!!!!!!!!!!

 

should anyone be in the great LA area and want to assist with this let me know. Happy to pay in beer

 

We performed this repair on our 2000 XJ8. Sent the part out for repair and quickly returned to us. After install the error messages automatically cleared. We have had no problems since. Our Jag dealer told us their charge for installing a 'new' $850.00 part was 300.00

I think we came out on the better end of this deal.

 

The windscreen washer reservoir is on the right side and the ABS module is on the LEFT.

How would removing any part of the reservoir help?????????????????

The X100 (XK8) has the fill neck in that area but this is the sedan forum.

bob gauff

 

I had to make a tool to get to the bottom two torx bolts. I drilled a small hole through the socket and slid a rod through to turn it. There was no way to get a ratchet in there between the frame rail and the ABS. But, everything is fine now and all it cost me was the cost of the sockets - which are not very common, but no big deal.

 

I do not want to speak for ECHOHARPER but I think he may have meant removing the coolant overflow reservoir. That is what I did after reading another forum member's procedure. The only problem is that it does take just a bit more time because you have to jack up the car on the driver's side, remove the undercarriage plastic shield to expose the reservoir. Two bolts hold the reservoir in place to the frame. Then remove the 4 bolts holding the ABS assembly to the frame. At this point you can lift the ABS assembly out of the frame to clear the 4 male bolts and move it a little to the left (even with the hydraulic brake lines still attached). You now have a lot more clearance to remove the 4 torx screws that hold the ABS module to the entire assembly.
Also while some chose to use hack saws, screwdrivers, or chisels etc. to open up the case, I used a dremel tool which seemed to work fine. Used E6000 to glue it back together. I also removed my brake lines because I was spending too much time trying the bend the lines enough. I did not break any speed records with my experience but now that I have done it, I think I could get through the entire process in an hour.
My car is a 2000 XJR. ECHOHARPER's car may be a different configuration. I completed my job 10 days ago and have not had the ABS light since then when I was getting it on a daily basis.
I do not mean to sound like my procedure is original. Others have done a wonderful job of describing that for our benefit and I thank them all.

 

I did this exact process last night, worked perfectly. The only other thing I would like to add is that having this tool makes it a lot easier and more comfortable.



It's a rotating ratchet. One of those tools I have but rarely pull out. When you twist the handle (like a throttle) it moves the head the same direction the ratchet head is set for, regardless of how you twist. In the tight areas of the ABS module, being able to remove and insert bolts at a 90 degree angle is a big help.

Start to finish, process took ~20mins

 

Thanks for the write up. I'll be doing this next week, after the tensioners, and after the fuel pumps.................

 

I have a question. I did the fix about a year ago, and recently have been getting the same error.

I have some mad soldering skills from years of doing it in the Navy.

I cleaned the joints before resoldering making sure the joints were not cold joints and there was no pitting.

For those of you that have performed this fix, have you ever had to do it again?

 

I added hot glue to pot the connector a bit to to stop the cause of the issue in additional to fixing the result.

Distributing the load back to the board with any non conductive material should lengthen the fix time.

 

i agree not too bad of a job

 

Have not had any re-occurance of the issue since this fix.

Do check that your magnetic wheel speed sensors are not bridged on the sensor poles with any metals particles. They should be pretty clean.

 

I pulled the electrical connectors to the module, blew them out with a can of air and plugged them back in. The codes are gone but who knows for how long. I plan to get a can of aerosol silicone dielectric lube and give the contacts a shot just to be safe. I have an XK8 so the advice on the washer filler neck is quite helpful.

Update: Spoke too soon. Made it about 1 mile before the problem came back.

 

FWIW those 4 little star-headed screws seem to be Torx E-5 size. I'm sure everyone has a set of Torx E-sockets. I don't.