Our 2002 XK8 has been sitting for about 1 month and when my wife went out to go to the grocery nothing but a single click and the warnings ACS Unavailable, TRAC Unavailable, etc. Would dirty wheel speed sensors keep the car from starting? Don't think that's my problem and no Jag dealer nearby for service. The battery is fairly new - maybe 1 year old. I'm thinking maybe something shorted out but am at a loss about what/how to track that down.

 

The car must be moving for any wheel speed sensor issues to throw warnings. When these cars sit around undriven, their fuel pumps seem to bite the dust. That may be your issue. But do not discount your battery dying, even at just a year old. When they sit, they fade....

 

Go back to the trunk and take the cover off of the battery compartment. Grab the positive cable and just wiggle it back and forth. Then do the same with the negative cable. I bet your car will start.

Several members, including me, have had problems with the battery cable. The battery is fully charged, but a loose connection inside the cable prevents enough current from flowing through it to start the car. It will allow the lights to come on, but as soon as you turn the key to start there's a pop sound from the trunk and the traction control lights turn on (etc., etc.)

Just try it and let us know what happens.

 

If you have a voltmeter, check the battery voltage. Below 12.4 or so is not going to make it. If you don't have a meter, either take the battery to Autozone for a charge, or jump the car according to the owner's manual. These cars wear down their batteries quickly.

 

Big thanks to Rev Sam. I had same problem last week and booked Jag into dealer but then found this really useful tip and tried it and it worked...so far so good. Only problem I encountered was front left bolt had seized and sheared when I tried to remove so now have that to deal with but car is 9 years old and previously spent it's life in a wet Scotland so not surprising to find corrosion on bolts. Thanks again for brilliant description with clear pics.

 

Just completed this on my 1999 xk8 and it looks like it fixed the issue!!

Cheers!

 

Thanks a million for the really detailed instructions on how to remove & clean the wheel sensors....if I could just let you know my progress, maybe you could offer a bit of advice, as it didn't go 100% smoothly!

basically, the problem I was getting was ABS light on, and DSC warning and amber light flashing (not solid). Whenever I got above about 25mph, the car would go into "limp mode", with no power (at the throttle) until the speed go back below 10mph.

The power then came back but this kept happening...you solution sounded perfect for what sounded like the cause of the problem.

I managed to remove and clean the rear wheel sensors, but unfortunately, the two front sensor's bolts look like they are corroded and I cannot get any wrench or ratchet to grip the bolts to remove them, so I am unable to remove and clean the front sensors...

Unfortunately, just cleaning the rear sensors hasn't fixed the problem. I still get the ABS light coming on and the DSC and flashing amber light with limp mode kicking in above 25mph.

Neither of these lights are on when the car starts, they only come on when the car hits the "magic" 25mph...

Any thoughts or advice would be extremely welcome!

Am I now limited to taking the car to a garage to see if they can remove the sensors? There really is nothing to grip to try and remove the front bolts!

Thanks again for the great instructions and video

 

Have you looked at the pressure in your tires and or the tire size? The ABS takes a pulse reading from each wheel and an uneven rotation could cause this. I have a test for a 99 xk8 that might be of help see the attached.

Link JagRepair.com - Jaguar Repair Information Resource

 

I always appreciate any new ideas, thanks...

I did have 1 new front tyre fitted a few months back, and I wonder whether they did something (or didn't do something) to upset the balance?

It was done by one of those mobile tyre fitters, as I couldn't get my car to a regular tyre fitter...I wonder...Hmmmm

How could I check?

Could an unbalanced tyre cause both the ABS light and DSC message (along with limp mode)?

Thanks for the tip

 

Not sure about a balance problem but proper inflation is important. I would try a hard reset first and see how things go.

 

I am going to sound really dumb now, but how do I perform a hard reset, and what is it designed to achieve?

Thanks!

 

Ah, just found this excellent post...

https://www.jaguarforums.com/forum/x...ect-faq-74146/

Could I ask a few quick questions first though please.

1. I actually disconnected the battery for a couple of hours and just re-connected it. I take it this wouldn't do all that the Hard Reset would do?

2. Can I just check...as far as I can see from the battery, there are only two cables connected to the battery, the positive and the negative...Can I just double check, I remove the cable connected to the battery negative terminal, and connect it to the battery positive terminal for 10 seconds?

Thanks...I will give it a try and see if it re-sets some electronics that might be causing my ABS/DSC issue

 

Just disconnect the negative terminal and Hold it against the positive terminal. It does not need to be connected and the positive cable can stay in place.

 

Thanks for that.

Did the hard reset last night...everything reset, as expected, went through the hard reset/batter removal procedures as laid out by Jaguar, but unfortunately, my DSC light came back on again once I hit about 20mph, and went into "limp mode".

So, I now have to get the front 2 speed sensors removed and cleaned and see if that fixes the problem...

So annoying, as I can't even drive it anywhere (to a garage) to get them to look at it, as the limp mode means I can't really drive it anywhere on a main road.

Ah well, I'll persevere...

Thanks

 

Just be careful removing bolts on sensors as I had a corroded one on the front that sheared when I tried to remove. It even ruined a new screw/bolt remover...very stubborn. I had to improvise by drilling new hole and replacing with a stainless steel self tapper to refit but if you can get behind bolt spray into hole with WD40 or something similar before you try to remove it might help loosen? Good luck!

 

I have organised a breakdown service to pick it up and take it to my garage on Wednesday...I'll get this problem beat, if it kills me!! (or bankrupts me...whichever comes first! lol)

 

Thanks much Rev Sam, I have this issue on my "99 Bentley, no doubt the same procedure so here goes.

 

There are other products, such a "Liquid Wrench", which are better at loosening stuck bolts. One that I've heard rave reviews about but never used is called Aerokroil. You can buy it on Amazon, or just Google it and you'll find lots of places selling it. I think I actually heard about it right here on Jag Forums. There was a thread a while back.

Also, an impact wrench is great for removing stuck bolts because the shock waves break them loose. A bolt which would shear off by simply twisting on it is more likely to come out in one piece with an impact wrench, especially if you soak it with penetrating oil first. If the head breaks off with an impact wrench, it would have broken off for sure with a regular wrench.

And... if you don't have an impact wrench, put a closed-end wrench over the head of the bolt (preferably a 6 point, not a 12 point) put some torque on the bolt, and then hit it with a hammer as you try to loosen it. Of course, soak it with penetrating oil first.

 

I'll do all of the maintenance on your Bentley for free if you'll let me borrow for a few weekends this summer.

(The weekends when my wife is out of town, of course )

 

Sounds like a throttle body issue to me. you may want to start there. If it turns out the problem there are a few online remans very cheap.