Oh no ! restricted performance AND the CEL

[PTR200Jag]

Well all the connections are sound, I also purchased a Bluetooth diagnostic "thingy" and used an android app called "torque".... no faults showing still....

As its been off the road since May I decided to tax it today and then went out in it...... drove around 30 miles or so with several (fuel too!) stops in between... around half way into the journey the "restricted performance" legend disappeared.......
The cel was still showing though but the amber warning light above the legend display had also gone out...

As I suspected might happen the cel finally disappeared on about the fifth startup sequence during the trip out.

I just don't get it and its pretty obvious that Jaguars software is prone to spurious outburst of irrelevant data when the car is not driven for some time.... the battery IS FULLY CHARGED before anyone says anything !!!

ah well, hope to enjoy some trouble free time with her now.......

[mike020150]

We're all keeping our fingers crossed for you! Mike.

[PTR200Jag]

We're all keeping our fingers crossed for you! Mike.

Went out again yesterday.... no lights, no legend, ran like a bird... pity it doesn't run on bird seed though, 15 litres worth of Shells finest went down the hatch in about 60 miles!...

note to self; must try and keep foot off the loud pedal..

Jumped in it again last night for another 20 mile trip.... all clear !

[J44EAG]

An interesting thing noted on my S-type noted over the past couple of days, Shares similar electonic architecture to the XK8 from which it was derived.

Kicked down yesterday to find transmission drive lost and engine over revving with almost total drive lost. Very odd and disconcerting.

Had a good run over to Southampton today, switched off to do some business. Returned to the car, turned the key...nothing! Opened boot to look at battery and found the +Ve battery cable clamp had fallen off the battery!!! The clamp had ridden up the non parallel battery terminal. Not good. This despite the bolt being fully tightened. It is one of those thin wall original fit clamps with the large 25mm starter cables integrally connected.

So the job tomorrow is to fit one of my favourite Ford type clamps with a vertical 8mm stud and nut. I fit those on boats as I find them the most versatile and reliable types of terminal fitting. In doing so, I shall crop off the OE clamp and integral cable fitting and crimp on a conventional 25x8mm lug end to the cable. I wonder if I have been chasing a bad connection off and on for several years which caused intermittent issues and which has even resulted in me changing a battery.

Worth us all really checking those battery connectors. They are not the finest OE product fitted to our cars. They are ok until something gives up. Then the trouble starts. Fault codes, DSC, etc,etc.

Mike K

[mike020150]

Jaguars are complicated cars but not all the faults are as sophisticated! Mike.

[PTR200Jag]

An interesting thing noted on my S-type noted over the past couple of days, Shares similar electonic architecture to the XK8 from which it was derived.

Kicked down yesterday to find transmission drive lost and engine over revving with almost total drive lost. Very odd and disconcerting.

Had a good run over to Southampton today, switched off to do some business. Returned to the car, turned the key...nothing! Opened boot to look at battery and found the +Ve battery cable clamp had fallen off the battery!!! The clamp had ridden up the non parallel battery terminal. Not good. This despite the bolt being fully tightened. It is one of those thin wall original fit clamps with the large 25mm starter cables integrally connected.

So the job tomorrow is to fit one of my favourite Ford type clamps with a vertical 8mm stud and nut. I fit those on boats as I find them the most versatile and reliable types of terminal fitting. In doing so, I shall crop off the OE clamp and integral cable fitting and crimp on a conventional 25x8mm lug end to the cable. I wonder if I have been chasing a bad connection off and on for several years which caused intermittent issues and which has even resulted in me changing a battery.

Worth us all really checking those battery connectors. They are not the finest OE product fitted to our cars. They are ok until something gives up. Then the trouble starts. Fault codes, DSC, etc,etc.

Mike K

That's interesting, obviously would look like a "battery fault" to the ecu too.
Just dashed out to check mine mines tight.... but I would be interested to see if your fix with the Ford type clamps... do we not already have those "Ford" ones on the Jaguars? , sorts your problem.

[J44EAG]

Not yet got around to this mod on my S-type, but here is a shot of the typical Ford clamp. I always install a rubber insulation boot over the whole unit to avoid short circuit possibilities.

Use of this type of clamp requires the OE standard fit +Ve (or indeed a -Ve) heavy load cable termination to be cropped off. The cable insulation then has to be removed by about a half inch and a 25x8 plated copper cable lug fitted to the cable. It is then squeezed with a heavy duty crimp tool to form a permanent fitting. The 8mm refers to the size of the hole in the cable lug end which corresponds in size to the vertical stud and nut arrangement atop the battery connector. The 25 refers to the cable size cross sectional area in square millimetres which on my S-type is of that dimension.

These battery connectors are easily available from ebay and other outlets. Avoid similar looking units which may have a tube and two screw fitting for easy cable fitting. The two screws are wound down through exposed cable and are supposed to give a reliable connection. In practice that frequently does not occur and a dodgy termination is often the case with this type of battery termination. Avoid like the plague in my opinion.

Mike K

[oyster]

Hi all.

Measured the temperature in my original battery cables with engine off and some high consumers on.
To my astonishment the temperature around the positive clamp was 50C. Ambient temperature 20C.
All other connections were ok.
Tightened the clamp fitting in a vice, but as you say, changing the clamps is probably a good idea.

[PTR200Jag]

Well here we are again.....the car has been running great, got gearbox oil changed, changed diff oil and the engine oil and left car in garage for two weeks, on charge, started it up today to get "restricted performance" immediately showing.

Drove to Preston, Supercars meet, 20 miles.

Leaving the meet I started it up, the rp was still there and then the engine light came on, following previous format of the problem. Hopefully it would correct itself once a few miles under the belt.

So ignored it and drove back a few miles.... still on ( )… then blasted “abs” light came on followed by “ASC, Trac control, a Restricted performance, on a continuous loop ! ( the cruise control works perfectly whilst all this going on.)

Stopped in a layby, discon the battery, recon, no change, lights still on.

Went home.

Stopped in drive got out and went in for cup tea!

Went back out started engine all lights out except restricted performance legend….arrrrrgggggggggggggggggggggggggggggg

Plugged in ecu interface,,,,, no fault found.

Then lights came on again….. nooooooh

Turned off engine, discon the reader…. Left it for few minutes to open garage doors and put it back into garage…. Started up NO FKIN LIGHT ON DASH .,…. What?

Drive into garage only thing showing is restricted performance……..

I give up……….
not even sure where to start now....

[Orkney]

My gut feeling is still centred around a slightly raised resistance being seen by one of the modules. With milliamps (and in some cases microamps) of current flowing in some of these sensing circuits, only being pushed around by a potential difference of 12 volts, sometimes far less in logic circuits, then even a small increase in resistance at a connector or earthing point could be read as a change of state causing error messages. High relative humidity, as we have at the moment (97% today in Orkney) does play havoc with connectors, only to stop showing faults once the air is a bit drier.
I'm not familiar with the common connections on the XK so does someone have detailed knowledge of the architecture of the system to pinpoint a likely common connector for this particular bunch of faults?
If not then it's a case of checking each connector and especially the earthing points. Abs and trac will certainly be using changes in wheel speed from those individual sensors and brake pedal switches will be involved too but I can't see why restricted performance should be invoked. That said, I can make that come on on my Daimler when using the J gate if my battery is low, which yours shouldn't be!
Ian

[mike020150]

One common switch responsible for plenty of false alarms is the gearbox rotary switch. With all the damp weather of late, it's probably had to survive much dousing. A good clean with WD40 or similar wouldn't take too long and may just generate some more clues if the situation subsequently improves. Mike.

[PTR200Jag]

Gearbox rotary switch?
Is this under the jgate ?

[aaj]

Peter

I've had same error messages but also get "Gearbox Fault" message

Error turned out to be the 'drop' lead to the Front Wheel ABS Sensor, 1st one side then the other.

One or more of the wires 'makes & brakes' as you turn the steering wheel or the suspension moves up & down.

You may find this is your problem

AllanJ

[doug424]

Hello PTR200 Jag.

The gearbox rotary switch is outside the cabin on the side of the gearbox, though I can't remember which side. I am on my third switch which Dave Marks told me some time ago is a poor design as the cable inlet is on the top where it is guaranteed to allow water in.

So long as you can get the car off the ground changing it is reasonably simple. I am fairly certain there has been a thread on this topic.

Doug Barrass,
Ashford, Kent.

[oyster]

Hi all.

I have been following this thread with great interest. Some comments from me:

These cars (X100) are between 10 and 15 years old. Electrical connections will corrode over time and lose conductivity. All connectors should be opened, sprayed carefully with electrical cleaner (not WD40) and reconnected. Same with all fuses and relays connections.

All ground points should be inspected, cleaned and tightened. Gnd. points underneath the car are especially prone to problems.

Battery clamps and cables, both negative and positive should be changed. The originals are thin walled clamps and the cables may corrode internally without any visible damage.

A generic code reader will not read specific Jaguar codes, e.g. wheel speed sensors, transmission etc. For that you need a WDS/IDS. (World Diagnostic System/Integrated Diagnostic System) Don't trust the codes blindly. A failure indication of a component may be a bad connection. Codes vary with MY. and VIN.

Throwing parts at a problem not completely identified may be an expensive game.

Some dealers are not very interested in working on these cars and lack the required skills. Try to find a recommended independent if you are not able to do the maintenance yourself.

ALWAYS DISCONNECT BATTERY WHEN WORKING ON ELECTRICS

I have had my share of problems, but it's still the most fabulous car I have ever had. British engineering and design at its best