Hi every,

After a bit of advice if possible for a strange electrical gremlin. its a long story so apologies, and strap in

so started to get restricted performance on my 2.7 xf and dsc not available (no engine management light), so I purchased a copy of sdd, and read the codes. there were tons on there, however there were two that tied in with 2 seperate instances of restricted performance. These were u0401-08 and u0401-68. These are both "invalid data received from ecm/pcm", one originating from the abs, one from the tcm. the battery was not great so replaced that and cleared all codes. However it came on the other day again, the following day when first starting the car I also got parking aid unavailable but the camera still worked. Got home read the codes again, attached below is a screenshot of the current codes. Now once again the same two codes came on, whats interesting with these ones is that this time on the snapshot data it is showing the voltage as being 11.5v, I pretty much immediately stopped and started the car to clear the fault when it happened so im 99% certain that this is a false reading as the car didnt even struggle to start. Alternator shows 14.9v and the batteries brand new and charged before fitting.

I am leading down one of 3 potential causes:

1. boot harness damaged - the sudden occurance of the parking aid unavailable is leading me to this, the question is though does the can network run through this? or could a potential short be causing spurious can-bus messages? I do quite alot of work with industrial can networks an know that it doesnt take much for strange issues to happen.
2. wheel speed sensor - kind of a stab in the dark, but it seems to come on more frequently in the rain, and wheel speed would be data required from both abs and tcm modules.
3. after doing some research on here around u0401 codes, i found the electrical drawings for the 2012 xf, assuming these are similar its showing at the end of the can network it shows abs -> tcm & ecm, seems a bit too coincidental to not be related as these are the modules showing the fault, so potential cable damage between these?

Any help on this would be greatly appreciated espescially with the sdd stuff, I did find on the snapshot data that it says "engine status (this value is invalid) = 0" which made think thats the error, however going through historical faults this even appears on the DTC for one of the door locks which has been faulty for over a year, so maybe a red herring.

Going to take a look at the boot harness on sunday when I have some child care, but any thoughts on this would be awesome.

Thanks

Rhys

 

I think you're on the right track, bad sensor and the wet having something to do with it, but unfortunately you will need a dealer level scanner to really get you to the "Invalid data" culprit.

 

can you post the electrical drawings? I've been searching and unable to come up with them

I have a similar issue. Dealer told me there is a main cable that runs through the middle of the cabin that is a known a weak point.

 

Hi BigWill,
What would you consider a "dealer level scanner"?
I'm asking because I am planning to purchase a more "serious scanner" (not just for this car) and I was looking at an "Autel MaxiDAS DS808". Would that be like a dealer level scanner or still just a sort-of an entry level thing but with better options?

 

I've used the MaxiDAS DS808 my friend had, it's amazing and does everything the Jaguar SDD does, but with a much better UI, which is quite hilarious.

However, the DS808 I ordered had a faulty cable which had a short or something and caused loads of modules to reset when I plugged it in the OBDII port! I swapped it out for the MK808 because apparently the only thing the DS808 does on top of the MK808 is key programming, and I figure I could use the Jag software for that on the rare occasion that I need to, and the MK808 is almost half the cost.

Sadly, the MK808 I ordered to replace the DS808 also appears to have the same cable fault, so I'm in contact with their support at the moment. My new MK808 works fine with my friend's DS808 cable, so it's definitely the cable at fault and not my car.

Even given my experience above, providing I can get the cable issue resolved I'd still recommend them.

 

Thanks for that info!
The only reason I want the DS808 is because it gives you the ability to program keys. Kind of need another key since I only have one.

 

In which case go for it. The interface is far better than Jaguar's own SDD.

 

I just purchased the MaxiDAS DS808 and for the life of me cannot get it to communicate with my 2010 XKR? Granted, I have only had it for 2 days but it still won't connect with the Jag. I can connect it to other vehicles I have and it communicates just fine. I downloaded all of the updates, but it still has me puzzled. I thought it might be the cable on this one causing the issue, but since it links up just fine with other vehicles I would assume the cable is fine. Unless I am missing something? I too only went with the 808 because I wanted the ability to add new key fobs to our company vans. Otherwise, i would not have chosen the other model. Is they anything special that needs to happen when connecting to the Jag? I've tried just plugging it into the port with the car off; with ignition on and with engine running, but no luck? Any advice would be greatly appreciated. Thanks!

 

Hi jeffu,
did you succeed in connecting the OBD? WHat was the issue?
thanks
-chris

 

Hi Chris, Yes I did finally get it to connect. The ODB fuse on the car had blown. I replaced the fuse and the tool was able to connect no problem. I should have provided a status update in the thread, so my apologies for that. So far I have been very happy with the MaxiDAS tool.

 

Did you find out what was wrong in the end? I have the same issue with my car.

 

Yeah bizarely it was the fuel filter, a few people suggested it, for the sake of a couple of quid changed it, and all's been good since.

 

Thank you for replying. That is bizarre it could cause those issues. Like you say, for the sake of a few quid it’s got to be worth a try.