Hello,

I hate to be posting only troubles on this forum from the day I got here, but I cannot get hold how this car is designed and local Jaguar dealer is absolutely out of this galaxy when it comes to anything other than selling new cars, so...

This morning, I started the car and went to work (no hard start or anything, car worked like charm). Stopped to buy coffee, parked the car. In 3 minutes (at most), I came back and the car will not start. Gearbox Fault, DSC not available, Air Suspension fault and Parking Brake inoperable faults are displayed + red light is on at the top of engine temperature gauge. Before I parked, there were no faults illuminated, car behaved as it should, A/C worked, audio worked, no noises, or anything other than normal.

I left the car at the parking lot and came to work on Taxi... Anything I should check first? I am planning to get there with my other car and swap the battery to be sure it is not the battery that died (although there is not even one symptom that might indicate low voltage - headlights work well, light is bright, interior lights works, windows go up and down with usual speed...). Any other suggestions?

Edit: Car is 2004 Jaguar XJ6, X350

 

Check if the lights in the J-gate / shifter are illuminated. If it's in park, the P should be lit up.

 

OK, I will check this. What happens if it's not?

 

Faulty J-Gate, which can cause all the faults you describe.

 

Update: P lights up. I tried to use cables to connect battery of a different car (2010 Prado) and still nothing happened. Same faut codes, nothing happening when I turn the key...

Another update: checked all fuses and installed new battery. Still same problem. Now ABS fault is also displayed. That red light on top of the temperature gauge is also lit.

 

Next step is to get the codes read
I suspect you will find you have can bus issues and if so start working though those.
Also pay attention to the modules that are not found in SDD

The IC will give you XMAS lights as you describe if it is getting no or bad data on the CAN bus.

You can try a jiggle of the cables at the Jgate and ABS and see what happens but really you need to start with an SDD session

Cheers
34by151

 

I am trying to get some code reading device ti my car this evening. I hope that can get at least some info out

 

I would also suggest you take a small tool box and look over the ground points, i.e. clean them. There is a Forum thread that shows where they are located. If the battery is good (fully charged) and it doesn't start in Park or neutral, I would hope for a bad ground. Does the J gate shift through all the positions? Also check everything that uses power and see what happens when you try to start her? For instance do the headlights come on brightly and then dim when you turn the ignition? Good luck. I hate working in a parking lot. Especially on a Jaguar.

 

IHeadlights, horn, side windows and everything else works fine.
I am unable to shift from P to any position even with key in position 3 and foot on the brake pedal. Only way to shift it is by taking off the cover and manually pressing some strange lever inside the J Gate.
The parking brake disengaged as soon as I reconnected the battery, now I do not have that fault lighting up. ABS fault came as substitute )

I will try find ground points and clean them later today
Doing something with a car on a parking lot of 24 hour coffee shop on the busy street is a real nightmare

Edit/Update: the generic launcher from the garage was unable to communicate with engine ECM. Gearbox, ABS and other modules displayed same fault - cannot communicate with engine ECM. It's the engine ECM or connector to the ECM that seems to have a problem. I will try to take the car to somewhere else on weekends, disassemble the interior part to see all the connectors and ECM unit itself. I am feeling optimistic, maybe it's just the connector and cleaning will help

I will post update as soon as I get things done. Thank you all for your help

 

One more update:
I used tow service to take the car back at my home parking before I could find any garage that might help. Anyway, the car was put on the tow truck and when rolling it down to parking, it started!
No lights, no errors, as if nothing has ever been wrong. I let it idle for 30 minutes - ran fine. After turning off, the car had same errors on the dash that I have described and no start. I tried to turn key on and of from position 0 to position 3 and at some point, there were no errors and car could start fine.

I still avoid driving it to work, but if it starts, it can be driven. I drove around 150 KM without turning the engine off.

My friend offered me to see if the ECU connector is bad or anyhow damaged (maybe water damage?), so we took off the cabin filter housing and the plastic thing where the cabin filter is, but could not unscrew the central bolt that holds the connector in place. I even damaged the plastic cover of the connector while trying to take it off...

How do I take this bolt off? Can it be a different thing going on than a connector or the ECU?

Any suggestion will be helpful, as local dealership has no idea about how to service X350s...

PS Driving Ford Explorer as a substitute car, so I am desperate to sort my Jaguar as soon as possible

 

Greg,

I had a similar scare a couple months ago with just about every possible warning light being displayed and the car not cranking at all (I went through the troubleshooting process, battery, fuses, etc; very stressful). This happened to me after re-installing my ECU (after sending it to UK for a tune). At first I thought that the tune messed up the ECU, but it turns out I didn't plug it in tight enough, so it was a connection issue. After reinstalling, it started right up just fine.

If you already ruled out Cambo's advice, then I would definitely check the connection to the ECU. Could be loose? Could be water damage? Either way you will need a 5 point torx bit to remove the tamper proof fastener.

I bought this set on Amazon for cheap, if you have prime membership it arrives fairly quick as well. Hopefully its something simple. Keep us posted

 

I know this sounds improbable at this stage, but I would not be too sure your battery is good. Have it tested under load at your local parts store and if it shows less than 13V, change it. Also, if the battery is good after testing, check battery ground first. Also, - just because it can cause all kinds of confusion, check the two bolts holding the gear change cable under the car are tight. Very easy to see and check
Steve

 

jazzyjags - Thank you for the hint. I have Torx keys, but mine have 6 point, didn't know there was anything like this...


I did try installing battery from 2009 Toyota Prado and once again from my wife's Explorer. It did not help. I am sure it has to do something with the ECU or the connector...

 

what did you end up finding? I have the same problem with my 2007 XJ Vanden Plas.

 

There are a series of three 450 amp fuses in the trunk.
Follow a thick wire from the battery to the rear of the car.
Take off the cover to see if they are still good.
Check them with your ohms meter.

 

was it the connection or connector or was it the ECU?

 

Hello to all and thank you for trying to help. Unfortunately I had no time to take care of the issue and left the car sitting until about a week ago. I did buy another car (not a Jaguar, but even bigger headache, BMW) and now I am back to finding out what a hell happened with my beloved X350.

About a week ago, me and my fried decided to take the ECU out and inspect for visual damage. Unfortunately, it has water damage. The board is rotten (it has sandwich board, so it is impossible to repair) to the level that it cannot be repaired. It seems water got in there quite some time ago and simply ruined everything.

I went to Jaguar dealership for an advice how to proceed. They have no idea. Checked everywhere and found a website in UK who sells ECUs but there is a note, saying that I have to send mine and they should be able to recover information from my unit in order for the replacement part to work.

I discussed this with the Jaguar dealership in Tbilisi and they confirmed, that the ECU will need a flash, so it could read and communicate information from/to other units in the car (immobiliser, suspension and etc.), but they have no idea how to do it. The service manager told me that they can try system update, but if the ECU module is locked (software lock of some sort) that they expect it to be, they will not be able to do anything.

I really don't want to junk this car, I love it and care a lot. To this day I believe X350 to be the best looking sedan and it suites me 100%. Is there any way to revive her? there are several sellers that sell the exact same ECUs over ebay and I am sure I can get it, but how should I actually use it?

Any information or a hint where to find such information would be a true gold in this situation

 

ECU. Worst possible scenario

 

Can I make a suggestion?
I had a small accident with my old 2005 S Type R and got into a similar situation. There are a number of places that advertise repairing your ECU/PCM. It might be worth it to send it off and see if they can repair it?

The reason I say this is trying to swap the ECU/PCM is a bitch!! To prevent car theft Jaguar has made it very hard to do. It is possible and very experienced people on this forum like Cambo have done it. It also might be worth sending Cambo a private message and see what he thinks?
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I took it to several local shops that work on the restoration of such boards and all of them refused to take on. It seems water was in the ECU housing for an extended period of time (maybe a couple of years or more) and the damage is in between the layers of the board. It is rotten. They suggested mechanically removing the storage chip and put it on another, good ECU, but no one seems to know if such manipulation will work.

The Jaguar dealership suggested that there is a way to reset old ECU from another car and "update" it with specific data provided by the Jaguar itself based on the VIN code of my car, but they do not have the required equipment to do it. They also suggested that the ECU is somehow locked from the factory and unlocking it is not something that is possible for them to do.

Maybe a garage in the UK can do such a thing, but no one in Georgia.

I will write PM to Cambo, I hope he can help