S-Type electric woes

[stephenaw1]

Bought an 2000 S Type V6 SE in October 2012 with 90K and apart from the odd engine failsafe mode and a swivelling drivers seat things have generally gone well. However, today, power steering failed, ABS, brake failure light came on, traction control went off, courtesy lights stopped working, boot wouldnt open, speedometer stopped working and computer message stating fuel data malfunction. From wiring diagrams it looks like the problem is with the General Electronic computer module as some of the above lead to the module. I read somewhere that a battery disconnect may reset the module so I tried it and left the battery disconnected for about 20 minutes. When the battery was reconnected power steering was resumed, the boot opened and the courtesy lights work but thats all.
Is this a common fault or should I prepare for endless trips to the local garage and an ever open wallet.
Any solutions to fix my car would be appreciated.

[J44EAG]

Sounds as if the car has had a major electrical " event". Suggest a diagnosis at a good local independent Jaguar garage.

You have quite a collection of faults here. I`ve never heard of or experienced so many in one go. However it may all not be bad. If this collection of faults are all caused by one feed on the electrical circuits or from one module that would certainly make fault finding easier believe it or not.

Please let us know what you find.

Mike

[stephenaw1]

Local garage carried out diagnostic test and say the car needs a new alternator as it does not give out the required output. Therefore the GECM is shutting down selective items eg power steering , trip computer and courtesy lights. Will a new alternator be the answer? Hope so but bound to be expensive.

[Martec]

Hi,

We have also bought a MY2000 3ltr V6, back end of last year and a few weeks ago it started giving amber alarms and then a red alarm and limp home mode. Like you I disconnected the battery but then went into overkill of cleaning every earth and +ve point, plus fuses and relays pulled and refitted. Apart from the battery terminals and clamps being white with corrosion I found several of the earth points corroded.

The worse was:
Under the passengerside wheelarch near the fuel filter - which I think is an earth for the GECM
Under the drivers side wheelarch, similar position - earth for the starter motor
On the top rail behind the drivers side headlamp - for the headlamp unit but also another for ABS!!!
On the top rail behind the passenger side headlamp - for the headlamp unit

The method of earthing is to use an eyelet crimped onto the wires and bolted to the painted body. An earth is made by the screw head on the eyelet and the screw thread in the body. As I don't have tap and die for these threads they were well wire brushed plus the eyelet and refitted with copperslip (hopefully the copper content will assist contact in the thread, time will tell).

So far so good, this may help with problem, I've used a professional with his code reader (very good) and a cheap PC based code reader, not so impressive.

A nice car and worth persevering with, I wish you well, the quality of the guy reading the code reader is as important the equipment.

Brian

PS I have water on the floor below the JW header tank, does the A/C dump there?? Boroscope time.

[stephenaw1]

Just got the Jag back from the local garage after having a replacement alternator fitted. Everything has come back to life. Marvellous. Except there is now a traction control fault message displaying. The garage want the car back tomorrow to let an auto electrician have a go. Im tempted to do a disconnect and see what happens after a couple of miles as I suspect it is tied up with the previous low voltage situation but I suppose I'd better let the auto electrician do his thing as I'm hoping to drive to Essex from Sunderland tomorrow and I dont want any more problems. The only other thing I need to fix is the drivers seat as only the right hand side moves forward or back. The link between the front right hand motor and the left hand side ratchet seems to have come away. I can live with it for now. Still love the car.

[J44EAG]

Keep us informed.

Good batteries and charging are essential for a modern Jaguar.

Mike

[stephenaw1]

Replacement alternator needs replacing. Auto electric guy says it is faulty. Battery light comes on now as well as the traction control malfunction message. Jag is now in dry dock until a relacement alternator can be sourced and fitted. When it is done I am sure I will have many miles of happy jag motoring, until then I am using my wifes trusty PT Cruiser.

[oldtimer]

Hi Mike & Steven,
Do you recall an earlier post of mine about testing overhauled Alternators from suppliers just not coming up to spec. Very often reconditioned items are done at absolute minimum parts and maximum cost. It seems that nothing much has changed.

[J44EAG]

I`m lucky down here in Fareham. I`ve discovered a great set up on a local industrial estate with a time served guy who will tackle any electrical rebuild on starters or alternators. I even get to talk to the man when I take a unit in for check or service. He says he can rebuild most alternators or starters and not many get past him. On every occasion, a suspect unit has been back with me little more than twelve hours later.

Normally I can rebuild and check starters myself. Sometimes a unit delivered to me will refuse to come apart. I had one the other day which when left with me was just a solid mass of corrosion and misery. My guy worked a small miracle and I collected it resplendent in a coat of shiny black paint for just £54.

I get charged £10 to check over an alternator which gets run under load. A further £40 or so for a diode pack, £10 for a bearing or around £60 for a general rebuild. All done with a laugh, a joke and a shake of the hand when I collect. Top service if ever there was.

Mechelec is the name of the company in Fareham, Hants. Highly recommended.

The moral of the story is then, that there are still decent electrical wizards about locally. One just has to locate them convenient to your own location.

Mike

[oldtimer]

Now that sounds good

[stephenaw1]

Got the alternator checked over again today. Auto elec guy says the alternator is sound. However, still no speedo, trip computer, mileometer, ABS light on, Traction control off, power steering off, brake warning light on. The suggestion is now that there may be a speed sensor malfunction. Sometimes the speedo does come to life and at the same time the central locking activates leading me to think it was a power issue. But when I think about it, the door locks activate automatically when the car travels over a certain speed, so it is connected via the speedo and mileometer to the speed sensor. Likewise, the trip computer needs input from the speedo. Power steering, I presume is also dependent on speed. Things are starting to become clear. Now then back to the garage to check out a replacement speed sensor unless there is an easy fix that doesnt involve shed loads of cash.

[J44EAG]

Sorry to hear that. You are having a tough time with that car.

Mike

[Montana5]

Stephen, I'm no expert but not so sure power steering, courtesy lights, boot release and brake lights would depend on speed sensor. I noticed from reading all your posts that no mention was made of the Battery, ok assuming the experts you have on hand would have tested this, or perhaps not, other than that it could be corroded wires possibly behind the front bumper.

Doug.

[stephenaw1]

Doug

Thanks for the suggestion re wires behind the bumper, I will check it out. The battery was checked and found to be OK but that was last week and as I am becoming aware, that is a long time in Jaguar world. Since having the alternator changed the lights and boot lock works fine. Im hoping that the sensor is responsible for the other stuff. I am hoping to look at it myself and my dream is that it just needs a good clean. Could it be possible? Dreaming again.

[stephenaw1]

Decided to have the original alternator repaired at a local workshop specialising in starters and alternators. £50 later local garage fitted it and now speedo, mileometer, power steering and everything else has kicked in. Strangely when I picked up the car the garage said nothing had changed but after a run and several light flashing and messages appearing, things settled down. Not completely fixed yet though as traction control is still showing a fault. Still, cant expect too many miracles but it is lovely to have the Jag back.