I really doubt that your symptoms could be related to the wheel speed sensors. Sorry...

 

I've gotten the ABS/ASC warning and cleaned the sensors and the warning has gone away...only to return later. I pulled them and cleaned them again and did not receive the warning for several hundred miles, but has has returned intermittently. I've been offered to use a scanner capable of reading the Jaguar chassis codes. I may take the generous offer up as this may pin-point where the problem is; i.e. which wheel, which sensor or cable connection or in the module itself. I am really hoping it is not a bad solder joint in the module, and don't believe it is, as the problem is infrequently intermittent. So what I'm saying is don't be surprised if the fault light returns. Maybe just disconnecting and re-seating the connectors is all it takes.

 

It could be that short cable problem that was mentioned in another thread. When the wheel is turned hard to one side the cable is too short and it causes the connection at the plug to pull apart temporarily.

 

Probably an intermittant open circuit ...stress on a connector when turning, or a broken wire. Since opening and reseating the connectors (for cleaning the sensors) gets you some temporary relief, the former one seems more likely.

Having the scanner would be best of course, but even without it it's possible to isolate the bad wheel by doing resistance tests at that big 25(?) pin connector that sits next to the ABS module. (I posted some procedures a while back in one of the "ABS" threads.)

 

You bet I will stay here... I have even referred a few of my friend Jag owners. This was a great experience and I was just so pleased that I, ME, was able to fix my Jag myself. I went out today and ran all my appointments without issue. I grew an extra hair on my chest I am taking on rear brakes and rotors next. WHOA!!!

 

...dejavu, 4 years ago, that was my first DIY project also!

 

What a great post Reverend Sam! I wasn't looking forward to playing with the module. And pics are worth a thousand words. This is a great place to start! Simple things first. I've said it before, but, I love this forum! What a great bunch of Guys & Gals willing to share their experiences. Found this thread from a post on the xj8 forum.

 

Thanks Rae. I really need to update this with a video just to show how easy they are to get to. Others have pointed out that you can access the front sensors just by turning the wheels to the side. The sensors are on the front of the vertical link, so to access the right sensor, turn the wheels to the right. Vice-versa for the left. In my first post I said it took 90 minutes. I have no doubt that I could pull all 4 sensors, clean them, and reinstall them in 20 minutes now. Of course, I have MY AWESOME IMPACT WRENCH!!! (insert the "Tim the Tool Man Taylor" emoticon here). It really speeds things up.

 

Sam: Cleaned all wheel sensors tonight. The Stability Control message has been intermittent, so who knows if it's the wheel sensors or the module. The sensors were dirty though, fronts worse than rears. My sensors had 3 exposed metal strips that were gunked up, easy job as you've pointed out. Glad you made the post. The down side is, I discovered that all the rubber bushings (control arms) up front are shot.....subject of new post on xj8 forum. Enjoy reading your posts, very nice of you to offer to help the college kid on the xj8 forum. Been following that thread, I've got a 21 year old and it's nice to see someone willing to help a newbie. Thanks again. No doubt this helped.

 

That's what I'm saying for the whole forum and all the pics, links, videos, etc. The Jag forum should be like a library for us. ...And who wants to go to the halfpage-picturemissing Library?

However, I thank the powers that put on the forum. I get a lot of value from this forum. I'm just saying that it would be a little more Jag-oohR if the database was impeccable. I'm certainly willing to help out in anyway that I can. Including seizing Jaguar fanatics by the throat and saying "Hey man! It's just a car!"

 

Thanks Reverend Sam for taking the time to post this with photos. The instructions were excellent & easy to follow. I had high hopes since so many others replied that it fixed their warning light issue. Unfortunately, it did nothing for mine. 2000 XJ8. Intermittent ABS light along with alternating Trac not available/ASC not available message. Has been happening over two years. At 1st every few months & now typically once a week. When I cycle the ignition -- it goes away. A few days after cleaning all 4 sensors, I got the usual ABS, Trac/ASC warning light--so did not work! While I had the front wheels turned all the way & the wheels off I checked the wiring harness & no damage apparent & no slack issue.

I’d be tempted to check the ABS box & test the resistance as Dennis07 details earlier in this thread. But, I don’t know where the ABS box is or how to test resistance & what tool I’d need & what to do if the resistance is not ~1K Ohm on one or more of the sensors. I’m guessing to replace all 4 sensors is expensive -- especially if it turns out not to be the problem. I’m also guessing that replacing the ABS box is very expensive. Again, especially if it turns out not to be the problem.

It’s curious that my warning lights do not come on every day. Most often they come on 5 or 10 minutes into the drive after the car has been parked in the sun for 2 hours once per week. They have come on other times but very infrequenty. So, I wonder why. What is it about sitting in the sun vs. the garage makes the lights come on after 10 minutes of driving.

Strange.

 

icon, look through the older ABS threads related to the C1095 Hydraulic Pump Motor failure, try here. That's classic symptom for the internal circuit issue. Rebuilding is a viable, affordable option for sure.

 

Your problem being so intermittent, while a PITA to troubleshoot, is probably good news, $-wise.

A bad sesnor is unlikely to cause this. A bad solder joint in the ABS box is possible, but my bet is the front sensor wiring and connectors. (I did see that you have taken one pass at this).

It can take very little stress on one of the connectors to create a fault. Also, not uncommmon is a broken wire inside one of the flex sections of wiring leading to the sensors (not an expensive part). Either of these two can produce exactly your symptoms.


Suggestion: open each front sensor connector, spray the bejezzuz out of each half with contact cleaner, let dry, reseat firmly.

Remember that if the ABS icon is lit, this may be a leftover from a past event ... only the "ABS / TRAC not available" warning says something is bad now.

 

I would also add that the little cog things that rotate past the sensors should also be cleaned. The front ones are easy, just spray them with brake cleaner. The rear ones are a little harder. They are surrounded by a bell-shaped housing. You can spray the brake cleaner through the hole where the sensor goes. Rotate the wheel as you're spraying so all of the little cogs get sprayed. You have to have both rear wheels up in the air at the same time to do this because you're turning the rear axle. If one wheel is on the ground the other won't move.

About every 4000-5000 miles I get this problem. I clean the sensors and it goes away. This last time I did a rather half-assed job and I still get the error on the dash about once a week. Prior to cleaning it was happening almost every time I drove the car. I didn't take the effort to spray the cog thingys the last time. It's on my list of things to do.

Did cleaning reduce the frequency of the problem? If so, I think it's likely that your cog thingys just need a better cleaning.

 

Thanks for the replies.
My ABS light never goes on unless the Trac/ASC warning messages also appear.
It virtually always goes off again if I cycle the ignition. Rarely, I need to cycle a 2nd time. Usually happens 1x/week. After the car parked in the sun 2 hours. This cannot be a coincidence.

I do have an OBD II reader (Innova 3130) which ONLY reads check Engine light codes & does not read any ABS code.

I thought ALL OBD II readers do just that, none will diagnose any ABS light or ASC or Trac messages unless the check Engine light came on, is this correct? Or is it just consumer models for $100-200 that only read ck engine & the pro models for thousands read ABS codes as well? Now, after some quick research I think I may be able to get an ABS firmware update from Equus for my Innova CanOBD2 3130 so, it WILL be able to read ABS codes but may NOT work on Jaguar.

ABS Firmware upgrade for Innova 3110 and 3130 CanOBD2 Scan Tools from Innova Electronics Corp.



H2Oboy, While I cannot solder I would like to look at the ABS module if it is not too difficult to access. Just to see if there are any obvious issues. Corrosion, wires broken, etc. I do not know where it is or if there is more than one. If someone can describe the module or the location or even better post a photo that would be great. I hope it is easy access like some fuse boxes I doubt I would correctly use the multimeter & 9 volt battery at the harness to diagnose hard to find wiring problems. Measuring voltage through the ABS sensor itself? I’d need to see a DIY with Photos. Also I read the resistance is different for different MY & I’m guessing XJ8 vs. XK.

I have the XJ8 2000 ELectric Guide as a PDF & pg 24 shows locations for control modules & the ABS/traction control is near the front driver side under the hood. I just looked & see two fuse boxes, larger & smaller. Larger one closer to the front bumper. I doubt one of these is the ABS module.

http://www.captainjaguarscathouse.co...ec%20Guide.pdf


Dennis, I looked inside the small hood protecting the electrical contacts for each wheel sensor & they looked very clean. ABS light does NOT stay on if I cycle ignition & never on w/o ASC/Trac messages. If I am able to get a code reader that does read ABS codes, I wonder if it will have anything to read if the lights are not currently on? If I wait till it happens & then pull over & shut off ignition to connect code reader, when I turn ignition on the warning will have gone. So, I’m S.O.L. unless car stores the code as it does for Check Engine codes.

Reverend Sam, The cog things did not look dirty at all. They were brown colored (Oxidation?) Actually, the front sensors were not that dirty compared to the rear ones as others have noted. I’m in AZ USA so hot & dry. No driving through snow & zero rust. And the cleaning did not reduce the frequency of the problem. I just don’t understand how cleaning the cog things could have any effect. If the sensor reads the notches or sprockets in the cog, they are very visible. As a matter of fact, I don’t see how a dirty sensor itself would cause an intermittent problem like mine. I wonder if Jaguar techs at the dealer know or if they would just start replacing expensive stuff till it is fixed?


The fact that Jaguar mentions this issue in the owners manual telling you to cycle the ignition & if that does not clear the warning to take it to a dealer means to me that they EXPECT that warning to cone up, Probably some design flaw.

As a non-mechanic, I’m guessing that heat build up under the hood causes the issue after 5 minutes of driving. I assume once I am moving that air flow must cool the engine compartment some. But then again why doesn’t it come on immediately after sitting in the sun when temp would be higher than after 5 minutes driving? Also, why isn’t the problem more frequent in summer with temp 110 vs. winter with 70-80 temps? It HAS happened at night but rare & not for many months.

If I take it to the dealer, they may replace the wiring harness at each wheel with the sensors & the ABS module & charge me thousands. They probably will charge hundreds just to diagnose. I realize this is a worst case.

Thanks,

Steve

 

Steve, my code reader reads codes and you don't have to turn off the engine. I have a cheap ($50) code reader that interfaces to an app called "Torque" ($5) on my Android phone. It also gives me ABS codes, believe it or not. Here's a link to devices similar to what I have. http://www.google.com/search?q=elm32...q=0&oq=elm327+

With my code reader, I leave it hooked to the obdii port all of the time. I can use the Torque program to read real time info, such as coolant temp, fuel pressure, MAF volume, and lots of other stuff. It also displays codes as they occur. I don't have to turn off the engine and then turn it to the "on" setting as you do with some of the readers.

 

Steve,

Intermittent faults like yours can be a PITA to trouble shoot, but the good news is they are seldom costly. A very good chance youv'e got either one of the problems that plague front wheel sensor connectivity, or the bad solder joint in the ABS box.

Even though those connectors look clean inside, they remain suspects. Did you hit them with contact cleaner? Worth a try. And seat them tightly. This much you can do without even pulling the road wheels.


BTW, a single electrical fault or transient will light up the warnings, and they will stay lit until you shut down the engine. Then, on restart, they will be off again until there's another transient (the ABS icon may stay lit for a time, even if the warrnings are gone). So the behavior of the warnings you are seeing may not be too mysterious ... it's consistent with a marginal connection somewhere and these are often temperature-dependent.

 

Thanks again Rev. Sam!

Cleaned all 4 sensors, the rear ones were dirtiest as you mentioned. I resisted the temptation to squirt brake cleaner into the rear sensor hole; it looks like there's some U-joints in there and I don't know what kind of lubrication is on them...

I can report that an 8mm socket on a mini stubby ratchet works great for this job, although a regular 8mm wrench would be fine too, and that it can be done with all 4 wheels on the ground if you turn the front wheels appropriately and if you don't mind inchworming under the rear of the car for the back ones.

No more ABS/DSC warnings so far (note the ABS light was on the first time I turned on the ignition but went out and has not come back on).

I think I found the cause of my 65MPH shimmy too - the inside of one of the rims is bent about a quarter inch. I'm assuming that's enough to make it shimmyrific... Time to find a wheel repair place...

 

Thanks for the detailed description. This ended up being much easier than I expected and the pictures saved me a ton of time. My traction control failed indicator came on while on the way to the airport, and I thought I was stuck. When I returned the light was off, but quickly came back on again and again. I took about an hour and removed and cleaned all for sensors.

My XK8 runs like new again...Thanks.

 

Just curious about something... Did you by chance replace your brakes recently? Thanks!