Just thought i'd give you a update on the problems that prevented me from bringing my XKR to Lakeside Raceway for the Euro day held recently.

Background.
Saturday afternoon before the track day and I had just given the Jag a bit of a wash in preparation. Upon driving out the driveway i put it into drive and a fairly firm clunk was to be heard and it hesitated in pulling away from the spot. On the dash the message was displayed "Gearbox fault".

I read the codes when I got home and the only relevant one was a P0701, which was basically a catch all type gearbox code.
I reset the codes and started it up again only to find it immediately showing the same fault when selecting drive. The gearbox was then in limp mode and wasn't changing up or down from 3rd gear.

My plans of putting her through her paces on the track the next day just went out the window.

I did manage to get along on the sunday to the track but unfortunately with out the Jag.
Thanks to Clarke, i did get to ride along with him in his XJ6 for his two sessions. Great fun and very much appreciated. It was great day with a good bunch of blokes.



Diagnosis.
I managed to get the car to a transmission shop this week. I was dreading the news. Fortunately, the transmission codes weren't indicating anything terminal. Possibly it was related to another problem i have been chasing with the ABS and a C1175 LR wheel speed sensor error.

Lurking in the system was 32 separate trouble codes. only 3 had been visible to my obd2 reader. some were explainable others a bit puzzling.

As we didnt know how long these codes had been there, the expert advice was to clear all codes, including transmission and to see how it goes. ABS trouble codes reoccured immediately so that is first place to start.

That sounds more promising than a gearbox rebuild.

Its a bit of a shame that it missed the Euro Day but I had fun day anyway.
Hopefully next time !

 

This may help you with some background info on the codes
https://www.jaguarforums.com/forum/s...rmation-42164/

I can also send you the DTC doc with all the codes. If you dont have the JEPC and JTIS (parts cats and dealer manuals) if not I can send you the links just PM me your email

If you want to post the codes that came up after they were cleared I can look them up for you

I'd also advise you to get a mongoose cable so you can run the Dealer Diags (SDD) for yourself but if the car is driveable you can come up to my place where I can connect it to SDD for you.

As you have found out most codes are not read by standard cose readers. While many aftermarket readers can read some of the Jag codes few can read them all. In not sure if the Trans guy had SDD or not but you really need to get the codes from SDD before moving forward.

Cheers
34by151

 

Thanks for the update Rob, hope you get it sorted soon.
James moving from Sydney to Qld is a valuable asset to us up here with his time and knowledge being offered to members to help sort their cars.

This type of generosity is rarely seen these days. He already helped get Paul's XJS sorted the day before we went to Lakeside.

 

Thanks Clarke for the kind words

The way I look at it what goes around comes around.

Another option as well is I am going to have my car up the Dyno near the airport for a whole day very soon to do some tuning. You can meet me there and we can connect to my SDD while the work is ongoing

Im just waiting for my Trans kit and some filters that I will fit before getting on the Dyno. Ill be making some changes to the exhaust and the ECU tune as well as a carbon clean and doing Dyno runs between each change. I need to get the filters changed and the trans pan/oil flush done before the runs though.

I will be deleting the OEM x pipe (inside a muffler housing) and the center muffler. Then fitting flanges to the OEM rear mufflers and fitting some new rear mufflers that have a funky valve in them

After an initial dyno run ill get the carbon clean done and another run. Next will be the Exhaust and another run. Ill then swap the rear mufflers and do runs with the valve open and closed. Depending on the results ill either keep the new rear ones or go back to the OEM rear mufflers. Finally the ECU tune and some last dyno runs


Cheers
34by151

 

Thanks for the offer James. I might take you up on that at some stage.

I will probably also order myself a Mongoose cable.
I have attached the list of codes that were read but who knows how long any of them have been hanging around. Some came back immediately when they were cleared, so that is where I will start looking.


I'll be interested to see how you go with your muffler delete and dyno work.
I had been considering something similar as mine sounds a little to civilized.


Regards,
Rob.

 

Ok Bob I have looked at the codes and I think your gearbox is OK

I'm assuming the ones with a asterisk are the permanent codes
From the looks of all the faults you have a bad battery, possibly and alternator issue and wheel speed sensor that needs replacing.

I would not worry about the generator codes or the sensor till you replace the battery

Dont worry about the P1000, it indicates the codes were cleared but the drive cycles have not completed, once this happens the P1000 goes away and is replaced by a P1001.

Before you say but it cranks and starts fine let me explain
When you apply load, IE draw current the voltage goes down. The more current the lower the volts. IF the volts go under 12.2 The modules go nuts and throw all sorts of weird codes.
In older cars say an 80's/90's V8 the only computer you had was maybe an ecu. Most of these worked down to 8 Volts. You have dozens of computer modules all that need more than 12 volts.
When you cranked the old style cars volts could go as low as 10 and it would crank like a deamon, fire and run.
Yours will do the same but the modules will start firing codes

Do a quick test
1. Check the Volts before starting the car (12.6 is the minimum)
2. Keep the meter on the car and crank it, Check the volts don't go below 12.2
3. Check the battery date

Post these results or call/email me

Ill bet its a low battery (not a dead battery) thats causing a lot if the codes. This may be because its old or because if a generator issue.

If I was connected to your car I would next look at the data stored in the flight recorder ( the cars black box) and clear that

BTW the P0701 is not a misfire codes it indicated the TCM is in limp home mode this will most likely be the wheel speed sensor causing this.

Also the associated modules generating codes are the ones very sensitive to volts and most of them will be false. That alone tells me you need a new battery

So the next steps will be a new battery
You could try a conditioner but this will only be a short term solution

After the battery goes in check and clear the flight recorder
Check the charge circuit
Reflash the modules that had codes
Clear adaptions and perform the drive cycles (IE it goes from P1000 to P1001)

Recheck the codes and deal with anything else
Most likely the C1175 will remain and will need the LH Rear ABS sensor replaced but we need to deal with the other things first.

IF you
PM me your email I will send you the Jag docs for all of this

Cheers
34by151

 

Rob ,
I agree with James, probably not a gearbox fault. A mate of mine fitted over size off road tyres to his new Wrangler a couple of years ago and it threw itself into "limp home mode" stuck in second gear, the fault code came up as "wheel speed sensor fault". Cleared the code and put original wheels on, it didn't come back until he fitted the off road tyres again. He had the computer calibrated for the tyres rolling diameter and all good, so as James says possibly a faulty sensor.

As for the battery, My Jeep threw up the engine warning light/airbag light and drivers safety harness light 2 weeks ago. Got the code read and reset, the engine light was for "low battery voltage ". When I tested the battery was 12.5 volts standing, 13.4 with the engine running and 10.5 when under load from the starter, I assumed that would be good enough. The air bag light has been staying on sometimes since, I think when starting the car with the lights on now I think about it,since they come on as soon as you turn the key in the dark.
Wrong, Sunday I was playing around with the trailer lights after the heavy rain on Friday which must have got into the trailer lights. After having the Jeep lights and indicators on and off for 30-45 minutes the battery was completely dead.
New battery, all seems good so far.

 

Thanks guys.
I had already thought battery may have been a problem.
The current one is 2 years old.

I am planning on chasing the ABS issue for the moment.

Regards,
Rob

 

Let me know what has been replaced and done so far on the ABS issue

This can also be caused by the battery issue (corrupting the module config) which is why I said to replace it right away and we will do a reflash of the modules.

If that does not resolve it we then use the SDD to test the parts namely the signals to and from the modules which will tell us if we have a parts or wiring issue

Should be an easy fix once the battery is replaced and alternator is confirmed OK

Cheers
34by151

 

James,
where did youu get your Mongoose cable from.

I have see these V139 Mangoose Pro for Jaguar and Land Rover For JLR Mangoose pro V139 Support Till 2014

They seem to be one of the better sources that i can find.
Anywhere else that I should consider?

Hopefully i will get some time under the car on Saturday to look at the ABS.
I have already done replacement wheel speed sensor on the LR but it didn't fix the problem.
I will swap the sensors around and see if the problem moves or not.

Thanks again.

Rob.

 

This is where I got my cable from
V139 JLR Mangoose SDD Pro for Jaguar and Land Rover Support Till 2014

Make sure you get that new battery in, you may find the ABS fault goes away with the new battery.

Swapping the sensors may show some results even if you get the code to swap sides it may also be a wiring issue.

Once you have SDD running you are able to test the sensor which saves a lot of time

Cheers
34by151

 

James, I think those two sites that we linked are the same company.

I'll be ordering one tonight.
Which version of SDD do you run v139?

 

1.25 is the way to go but also have 1.41 setup but thats another story

Dont worry too much about the software we can sort that out once you have the cable

Cheers
34by151

 

OK - New battery installed.
The old one dropped to a minimum of 10.3v during starting even though it was sitting at 12.7v.

I swapped the wheel speed sensor between the two back wheels and the fault has moved from the left to right hand side (C1175 -> C1165).

Sensor impedance measures 1.1k Ohms which is correct but there must be something more going on.

I source another sensor and see how that goes.

Mangoose Cable is ordered so hopefully that will get me some better visibility into the codes.


Thanks for all the assistance.

 

Once the cable arrives we will get you setup

Sounds like you have found the sensor issue, a new one should fix that

Cheers
34by151

 

OK - so it look like it is all sorted now.

But what I found out was there were two different ABS wheels speed sensors on the X100's. The earlier models of XK8/XKR have a part number of LJA2226AA. There have 1.1K Ohm resistance and appear to be an analog type signal.

Later models have a part number of 2R83-2C190-AB and are physically compatible but electrically incompatible. I suspect these are a digital type of signal. Unfortunately most spare parts dealers don't know this and will send you the older one.

After receiving two different examples of the earlier sensor, I worked out that they were electrically different. I used a multimeter to compare these to the other working sensors on my car.

Of course there seems to be bugger all of these things in Australia at anywhere near a reasonable prices, so the delay in getting the shipped from the US is all part of the fun (not).

Finally got the new sensor and fitted it last night.
ABS seems to be working fully again.

 

Surprised to see this low battery voltage problem.
Even battery's in reasonable condition will drop battery voltage to 10V or thereabouts.
I have even seen car start easily from cold & drop voltage to 9 -9.5.
Pity to be forced to change a battery earlier than is really necessary because Jag failed to design with appropriate margins.
Can boost capacitor help in such situations, although I gather the cost may approach a new battery?