Alright been having this random issue lately, past week actually. The CAR RUNS then randomly get the message of ACS/Traction control not available, then failsafe mode (not restricted performance) engine failsafe mode to be exact.

It happens at random. Some days nothing happens other days it happens many times. Sometimes usually turning it off then restarting "solves" the problem" for a bit.

Already tried- Code reading-nothing comes up. Even Jaguar Dealership, when it happens and when it doesnt happen.

Connections were clean and tight even the little metal connections inside the plugs, cleaned anyways, nothing for the throttle body. TPS sensor switched no difference. Throttle body cleaned just in case it was the plate sticking no difference.

Switched out the brake switch, no change.

Side note: Come to find out it can and does happen at random even if the car is not started. To the point where all the dashlights are on, where it runs the system check, and sometimes it doesnt happen, and sometimes between 5 secsonds and 1 min, those lights as decribed above the ACS/traction control and failsafe mode lights comes on. Again, this is when the car is not even running.


Just had the battery checked, perfect condition they said according to the test.


I'm running out of ideas, the Jag dealership have no clue what to do now, and can drive nor depend on a car that I dont know if I'm going to make it across an intersection or not or make it home for that matter.

Hopefully someone else had this problem before and can help or else this will have have to be my last time on this forum and last time as Jaguar owner as if I cant solve this problem, then I'll have no choice but to sideline the car, depend on the Lincoln for a week or so, and find a 200-2006 S-Class or 7 series, cars that I am more familiar with and more information is readily available for. Hopefully someone can help or this might as well be my goodbye post also. It was fun, and the Jag is nice car and still would recommend it to anyone that have the absolute know how and or really want one but dont know the inner workings as well as other cars and cant find info to learn the inner workings well like with the BMW/Benzes. I dont want ot be an ex member of the Jag owner club either, the people are nice here, they seem to help when they can, and Jags are some of the nicest styled cars on the road today of any year. Only car I can think of with an absolute better interior than the X308 is the 1999-2006 Bentley Arnage/1999-2002 Rolls-Royce Silver Seraph, which I will get one when I turn 30 (BMW electronics and engine in the 1999 Arnage and Silver Serpaphs parts and very familiar with the 6.75 and GM transmissions so no issues on that level).

The Wolf.

 

Hi Wolf,

did anybody have a look at the ABS control module yet? I wonder why the dealership didn't check it, at least according to your report.

Did you try a forum search for the error message. A lot of threads with helpful hints should be found as this is no extraordinary or rare error message.

 

yeah, checked the forums and that's how I got the idea to check the stuff that I did. Not to mention 90% of them talk about it it being only when cruise control is engages to attempted to be engaged, which doesnt fit my problem much as it seems that whether or not cruise control is engages or not car running or not, my problem arises. One mention the throttle body stuff and that did seem to fit until I ran through the trottle body stuff which seemed to fixed their problem but mine still persist.

Not sure if they checked the ABS module or not, but they didnt mention checking it either.

Wouldnt a problem with that module cause the ABS light to illuminate also?

 

Fun fact. The ABS module and the Traction Control module are in fact, the same module.

I replaced the module in my car (the process of which introduced me to the "fun" of cylinder wash issues, but that is somewhat unrelated). It has not happened to me since, but I've only had the car back for 2 days, so I'm not sure if it actually fixed it yet given how intermittent the issue is.

 

so where can I pick up a good abs control module and what kind of work goes into getting it installed?

So you had same problem as mine and no problem since? But I find it odd that no ABS light is on. Not to mention never seen one have issue and not trip a single code.

Every single car I know from since the 1986 W126 MBZ to 1984 BMW 7 series to the 2007 MBZ S-Class and everything in between including the 2006 DTS Grand MArquis and 2011 Titan if anything at all goes wrong with the ABS module in any manner even if it's dirty sensors, trips the ABS light. And usually this isnt a cheap or easy to replace part and not a part I just want to throw a part at and find out it doesnt solve the problem when that money could've went into the new car.

 

The ABS pump fail code is U1094 I think, motorcarman (Bob Gauff) a member on here knows all about them, I wonder if he'd be able to help.

There are great threads in this forum on how to refurbish the module instead of trying to buy one...if you like a 'not difficult project' - follow the process to get it fixed. Or send it off to the refurb company in those threads, I think its $100 or so and guaranteed.

If the dealership only plugged in an OBD reader instead of IDS/Rotunda software and hardware then they wouldn't pick it up. If it flagged a light it must log a code, no?

Another thought, you already checked the connections/tps/brake switch, (you probably read a few of my posts) I wonder if your car was in the range that required the gold pin update to a connector on the throttle body, more on this in a TSB I think, but the cars effected usually cut out on the highway...

I ended up swapping throttles but grabbed a few P1121 from the obd reader, turned out it was a pedal position fail, and took a few limp's home, hard resets etc before I nailed it.

 

well there is no ABS light.


What is this pedal position sensor and where is it located?


So far, it never happened on the highway, usually only stop and go and or pulling away from a stop or light, parking spot and things of that nature when it does happen. Never at speed. And the car never completely shutoff or stalled.

It is a 2000 think June area manufatctured, most stuff been upgraded, like the tensioners and the upgrade to metal coolant housing from the plastic version.


I havent asked them what software and stuff they used though, but knowing them, they may not be equipped to read ABS code anymore than Autozone is. But again, there is no abs light on.


And Last time issue with ABS, it only tripped restricted performance mode and not the current engien failsafe mode (broken connector it was PITA to find a new wire that runs from the ECU to the module. NO ABS light since with the TCS/ACS restricted performance light since. From what I read, the car can and should be able to be driven near normal albeit wit hABS light/ restriced performance light during the time that the module is sent out for rebuild. Which makes the engine failsafe (again different from restricted performance) part the odd part.

But if it comes down to buying or doing anything with the ABS module, I rather go ahead and buy new because if it wasnt it or the repair doesnt work, a rebuilt opens up too many questions if I was to repost about here in the future. Then the questions would be did they rebuild it right, did they use the right parts, was it too worn to be rebuilt and etc and too many varibles added and loss of a lot of time for shipping rebuild shipping return to know if it was infact the ABS or not if the rebuild did not work and not to mention, havent had good experience with those "guranteed" rebuilds. They alwasy end up being a PITA to claim and usually end up with a faulty part still, loss of money, loss of weeks of times and or court proceedings. I'm not itchign to do that once again after done it too many times, more than three to be more specific. Instead of new one where it would be cut clean case of it wasnt the ABS module.



Come to think of it, a mechanic tha tI take my cars to have that IDS/Rotunda software and hardware. I just recalled that he said he bought that stuff when he was repairing a 2001 XK8 ABS system. Going to take it to him and see what comes up. Thanks for mentioning that. I almost forgot and wouldnt have thought to run by there, if I can make it, to see.

 

you're thinking too much into a simple repair, it's 2 blobs of solder, no parts, no fuss, you do it yourself if you've a soldering iron.
Hope your tech pulls something.

 

mechanic ran test. ABS module working perfectly. Nothing out of the ordinary came up. No error codes. Crap so it isnt that thing.

 

I'm not an electrician, so I can only guess. Looking at the Electrical Guide information for the ABS / Traction Control system (it's attached) I see two more possible cuplrits (anybody more knowledgable may correct me):

- there could be a problem with the wiring from the control module to one ore more wheel speed sensors.

- brake fluid level may be too low.

The break switch is already ruled out if I understood correctly.

Electrical Guide XJ 2001 ABS.pdf

 

Had brake fluid checked when they ran test on the ABS module. It's correct level and sure as hell not old yet.

But havent checked the wiring to the sensors. Will check that out and see what comes up.

Kind of stupid for engine to go into fail safe mode over an abs sensor instead of just going into restricted performance mode. Who thought that was a good idea?

Starting to think Jaguar was not the car for me. Too many mundane sensors that can cause the car to be undrivable when otherwise it still should be.

 

Instead of crawling around on the ground or floor to check the wheel sensors and their wiring, you can check them at the ABS/Traction Control Module plug with an ohm meter. By checking at the plug pin points you're checking the wiring and sensor at the same time. I've seen different ohm values at various places, mine were all at 1.06 and 1.07 ohms. When I went to my local junk yard I was able to pick up three there and they were the same, so I'm fairly confident they're okay. The pin points and the color of the wires attached to the points for your 2000 are as shown in the pictures below,

RH Front Wheel Sensor points 3 (yellow wire) 4 (green wire)
RH Rear Wheel Sensor points 6 (yellow wire) 7 (orange wire)
LH Front Wheel Sensor points 17 (white wire) 18 (red wire)
LH Rear Wheel Sensor points 21 (blue wire) 22 (blue wire)








I definitely know how you feel about your Jaguar. I bought my 1999 XJR back in 2004 and it's been a love hate relationship ever since. Unfortunately lately it's been all hate and I think once I get it running again and squared away it might be time to say good bye to it. I hate to do it, the car is a beautiful car but I've been experiencing nothing but an electrical nightmare, no start, ABS/Traction Control, Engine Limp Home mode, brake lights on continuously, radio issues, etc., etc., etc.

For the no start, I changed the battery, the key exciter ring, the starter, checked the grounds, checked the wiring, checked the starter relay, none of them helped. Of course when the simple starter circuit is made as complicated as it is on this car who knows what the problem is, a bad body processor module, ECM, VAT system. Then to be able to read and find out what the problem is I either have to spend $500 on laptop software to read the modules or take it to a Jaguar shop and probably end up paying close to $500 just to have them do so. Same for the ABS/TCM, I've checked all my wheel sensors at the wheels and at the module and the readings are all okay. I split open the ABS/TCM to check to see if my solder joints were bad, they weren't, so I sealed it all back up, and reinstalled it. It actually stayed clear for a while but the warning lights came back a few days later. I found a number matching module in a local junk yard, tried it, no go, as soon as I started it up the lights came on immediately. I'm pretty sure the center console Trac Control switch is okay due to the fact that the LED works when the button is pushed. For it to do so the switch is sending a signal to the module and the module is sending the on and off signal to the LED. The brake reservoir has fluid in it but I haven't checked the sensor itself. One thing that I haven't checked that just dawned on me is the brake switch. It sends a signal to the ABS/TCM, and I have been having problems with the brake lights staying on. Actually I think I remember seeing a TSB (technical service bulletin) about the brake switch in the TSB sticky. I'll have to check that out, it would be great to actually find out what has been wrong for all this time.

Today I got it started and thought I'd let it run for a while, came back a few minutes later to find anti freeze all over the ground. The octopus hose at the rear drivers side of the engine blew out. Then I realize that when the wonderful designers were designing the engine, they ran two of the rubber coolant hoses UNDER the supercharger. Absolutely marvelous! When the rubber hoses wear out you have to pretty much tear the whole top of the engine off just to change them. It doesn't get much better than that. Evidently they felt if someone was willing to spend $70K (what it cost new) for one of their cars, what the heck, stick it to them all you can. I realize my car is going on to 14 years old and it has about 80K miles but for a premium luxury car like a Jaguar (owned by Ford at the time), I'm very disappointed with the way they did quite a lot of things. And all the problems so many people have had with the various modules points to one thing, cheap junk, build it as cheaply as possible. If a company is marketing and selling something as premium, making it as cheap as they can shouldn't be their number one objective, because if it is, they're missing the point of it being premium. I've gotten way off course and didn't mean to hijack your post so I'll get off my soap box but I just had to vent a little. Hopefully the above info will help a little.

 

Anyone wanting to check their wheel sensors at the ABS/TCM plug, the wire color code changed with the years. At first I was going to post the schematic I used for my '99 then I realized the wire colors were different. The pin numbers should be the same. just different colored wires.

 

Yeah. I know what you mean. ANd it isnt age nor price because I have owned cars that was twice as old and about twice as expensive adjusted for inflations and about the same price without adjustment and had less problems and the problems that did arise was simple easy fix, and some was before the 'Make everything easy to diagnose OBD2 era." While some was mid 90s. The W140 was considered the most over engineered Benz a person could buy but even that electrical system with miles of wires literally and modules everywhere was less troublesome because very few made the car undrivable and everything was usually within decent reach, except a few nuts and bolts of strange parts but the normal routine stuff was dead easy to get to. Besides a few expensive parts and sticker shock at said part prices sometimes, they was fairly easy to work on, easy to diagnose. Although some electrical gremlins are a straight PITA to track down, very very very few cause the car to be undrivable. Usually worse case is a dash light. The major stuff was solid and dead simple. But compare pound for pound era for era, I think the W220 is better compare but even that car is more simple and cost more and just as old, and easier to fix and less things to leave you stranded or off/on problems. But the the interior has nothing on the Jaguar. The outside also I think the Jag has it beat. But really as far as the ergonomics of how things are done, it's a little puzzling on the Jag to me. Just stuff that was on any car make me wonder wtf. Like the plastic tensioners? what the hell. The most vital part of the engine, if any part where weight saving should not be the goal would that part but they make them out of plastic? And the A-drum thing but I think that is more of ZF's fault than anything for building weak A-drums. They been doing that since the mid 80s and still haven't seem to have learned. Probably why Jag had some sense and went with the more sturdy tranny for the XJR. as I would imagine that XJR would decimate the ZF A-drum within two seconds flat.

I remember when 14 years used to be considered young for a premium luxury vehicle. My 88 MBZ 420SEL is still going, the 88 5 series is still tinkering around town, the E23 of 87 was still kicking at over 260,000 miles before its demise at the rear end of a heavy duty truck. The 89 MBZ 560SEL was well into the 255,000 miles before having to be left in Germany due to me not having time to fix a simple driveline flex disk before being restationed and they wont ship any car that couldnt move under it's own power (long story). All those cars are and was well into their 20s and still goign with less problem. Now 20 years later, and some, a car struggles to make, especially luxury cars, to make 14 years and 100,000 miles with all the updated technology and stuff? I find it hard to believe that they do not design them like that on purpose so you can buy a new one and make them more money. I find it hard to believe that the electronics in the W126 ,and that car has plenty and more than some "modern" cars, have less problems mechanical and electrical, a system designed in 1975, than cars that is supposedly designed using superior technology and know how built up over those years?

 

alright the snowed has melted and got around to testing those sensors as described in the diagram.

Not it.


So far havent had it go into ACS/Traction control not available, then engine failsafe mode since the 6th of Jan but closer to but not there yet in finding out what is causung it. So far ruled out the sensors, the ABS module, brake switch, low brake fluid, battery, and the usual stuff. My problems are never that simple. My luck isnt that good. I wouldnt be surprised if in the end it's some ultra rare problem that only happens on two cars every three body styles.

 

What about the wiring, Wolf? Is it still to be checked or does it fall under "the usual stuff"?

Are all connections clean and tight? Are all wire coatings unharmed?

I remember a couple of threads in the BMW forums I used to visit in my E39 days which deal with ABS trouble caused by a spot of blank copper in a wire that leads from a wheel speed sensor to the module.

 

the wiring falls under the usual stuff. Checked as part of the bigger diagnostic.

I'm pretty sure if anything was going on with the wheel sensors wiring it would trip off the ABS light.

 

I am assuming here that the electrical 'plumbing' is the same as the XK series (and I could be wrong).
There are two brake pedal switches that have to operate in the correct sequence or they can trigger a problem like yours.
There's quite a lot on the XK8/R section about this.
If you haven't already downloaded the JTIS from your How-To section at the top then I strongly suggest you do.

 

Where is the other brake switch located. I just know about that one which is under the pedal which if inplugged the brake lights dont work nor the switch inside the gear selectoir set do not work and thus the the manual button have to be pushed with a long thn object to get the car out of park. Not to mention the associate beep device that goes off if the car is shut off while in gear and also beeps while attempting to shift from park if the key position is not in the run position i.e openthe door and trying to shift out of park without inserting key.

 

As I said, I'm no expert on the XJ's but willing to make a (small) bet they're the same.
Do have a look in the electrical section of JTIS.
ON XK's they are both close to one another involving a limbo dance.