hello am new here and need some help finding out what the problem could be.

i have a 2003 XJ6 3.0 Petrol with 160000 on the clock and i have had a small electrical fault with it for a while now it would sometimes show up with park brake fault or air suspension fault and the window wipers would slowly crawl up the window without even being switched on so i replaced the battery with a brand new one but that did not help.

today its gotten worse it happens most of the time now and it also shows an ABS fault which i have not seen before. the faults keep disappearing on the dash one minute the car is fine next its full of faults almost like the power is being cut on and off. it now has started to cut the engine sometimes when am driving and the power steering not working as well as it should.

this has become an issue i cant ignore any longer and would like some help on finding out what might be causing this if anyone could give me any insight on what this might be i would appreciate it alot thank you

 

Hi philj2050,

Welcome to the Jaguar Forums!

I'm sorry to hear you're having trouble with your Jaguar.

First of all, your warnings may not indicate one general electrical fault. They may mean exactly what they say. You may have an Air Suspension Fault and a Park Brake Fault that are separate and real malfunctions. There are lots of threads on both of these subjects so spend a little time in research to understand some of the possible causes.

The ABS Fault may also mean exactly what it says, and you may have a corroded electrical connector or ground stud, gunked up wheel speed sensor reluctor ring, failed speed sensor, or other problem. The Park Brake Fault and ABS Fault could also be triggered by low voltage while cranking, so even if you have a new battery, if corrosion in the battery power connections throughout the car lead to low voltage at the ECM while cranking, random faults can be triggered.

The windshield wiper problem could have to do with the steering column stalk/switch, which has been known to fail, or with some other part of the electric circuit for the wiper motor.

You can download and save the Electrical Guide at the link below to look for points in the wiring where the circuits you are having trouble with connect to the same component (fusebox, etc.) or are otherwise in close proximity.

http://www.jagrepair.com/images/Elec...al%20Guide.pdf

It is quite likely that one or more Diagnostic Trouble Codes (DTCs) are stored in the computer modules of your car, and scanning them would help you narrow down your diagnostics. It's often helpful to erase the codes, then re-scan to see which, if any, reappear. Many of us have made the modest investment in the dealer-level software-based diagnostic system, Jaguar-Land Rover System Driven Diagnostics (JLR SDD), which, in conjunction with an appropriate interface cable such as the Mongoose or Ford VCM, allows us to read and erase codes, program modules, re-calibrate the air suspension, etc. This forum has several threads on this topic as well.

Also, since we're a friendly bunch around here, please visit the New Member Area - Intro a MUST - Jaguar Forums - Jaguar Enthusiasts Forum and post an introduction so we can give you a proper welcome and also learn something about you and your Jag.

Cheers,

Don

 

I would start by checking the integrity of the earth connections in the boot area as the symptoms you describe are very similar to that of a dying battery (these cars are very voltage sensitive) but as you have replaced it then it would tend to point to an interuption in supply and/ or high resistance, are the terminals secure, is the battery the correct spec, are the earth points in good order. Simple checks if you have a multi meter. After all that is checked then I would start down the road of investigating each individual fault.

 

thanks for the responses i think its something to do with power transfer and not faults with the car. ive just been out in it and as i parked up i now have a new gearbox fault the car has now become drivable am quite sure its something to do with the power.

i have checked the battery is the correct one i have heard the earth points are prone to problems with this car do you think it could be that? maybe the alternator? i have no idea.

when i use the window wipers it cuts the cars engine out what can cause this?

where about the the earth points on the car and what would i be looking for i guess i can start there.

thanks again for the help guys

 

The earth points locations are given in the Electrical Guide on page 25 of the manual (page 27 of the pdf file). Note that most of these grounds consist of a threaded aluminum stud riveted or welded to the aluminum body of the car, with a large (13mm hex) nut that secures the aluminum eyelet or ring terminals of the wires to the post. The torque specification for the nut is a VERY low 9 nM / 6.5 lb-ft. Several owners who have forgotten to look up this spec first have managed to pull the threaded studs right off of the body by overtightening the nut.

Remove the nut and wire terminals, clean everything with a fine brass brush and zero-residue electrical contact cleaner spray, then reinstall the nut and tighten it to the proper torque. Do not use sandpaper or a coarse steel wire brush or you risk forming scratches in the aluminum which will only promote future corrosion.

Another common problem is corrosion on the battery power connections at the power distribution fuse boxes and elsewhere. See Figures 1.1, 1.2. and 1.3 in the Electrical Guide.

I would still highly recommend having your codes read, then cleared and rescanned to see if any of your issues are real, permanent faults or if they are all just glitches.

Cheers,

Don

 

Liverpool with lots of salt-laden air blowing in from the Irish Sea !

It might help to inspect and clean the earth points at the front of the car. These are behind the headlamps, and accessed by removing the plastic cover over the radiator. Carefully remove the securing nut, clean up and re-secure, then coat with a suitable anti-corrosion oil or grease.

The above applies to all earthing points where atmospheric damp and salt has access. Also get the fault codes read too.

PS
Have you checked the plenum chambers at the back of the engine compartment ? There are two easily removed plastic covers. Check drain holes are clear and there is no standing water.

 

Make sure that the positive and negative battery terminals are shiny and snug. It wouldn't hurt to shine up the battery posts as well with some fine sandpaper. If those terminals weren't clean, try driving the vehicle.

If the symptoms should reappear, disconnect the negative battery terminal. Next, disconnect the earth grounds in the boot and clean up those terminals. Reinstall those earth grounds, and reattach the negative battery terminal. Drive the vehicle again, and then see what happens.

 

hello again turns out it was the earth points. checked them the next morning and 2 of them just snapped off with a touch! rewired the earth points to another location and all seems good now. thanks again for the responses

 

Hey Phil,
I have exactly the same symptoms - which earth points did you find to be the culprits (of the 34)

 

I have an identical problem. Would you let me know too which earth points were the issue?

 

"It might help to inspect and clean the earth points at the front of the car. These are behind the headlamps, and accessed by removing the plastic cover over the radiator. Carefully remove the securing nut, clean up and re-secure, then coat with a suitable anti-corrosion oil or grease.

The above applies to all earthing points where atmospheric damp and salt has access. Also get the fault codes read too."

 

Sorted! I had a faulty Ground Point (G3 - top one behind driver-side headlight). It sheared off with no pressure at all as I loosened the nut. Relocated the two ground wire lugs to G2 below.