I made the trip home this morning without any issues after my "restricted performance" problem this past weekend -- and ran the codes on the XJR.

Originally I had no codes listed .......Then I ran them again and I got a P1642: "CAN Link Circuit". I always get this code -- I don't think the car likes generic code readers - It always goes away when you reset.

So - I started the car and went to read the live data just for fun and while I was playing around the restricted performance lights went on!! Reading the codes again I had a P1797:"CAN TCM/ECM Circuit Malfunction" ??

I ran them a third time and another came up P1638:"CAN Link/INSTM Circuit/Network ?? Also now had the P1000 code for the test circuit?

So I am thinking that the P1797 is the problem -- Any ideas??


Also -- another strange thing. I got a series of beeps from the dashboard as I started the car - this while I was testing it. I had turned off the climate control and after one of the starts I noticed that the display on the climate control was saying error while I was hearing the beeps -- So it was the Climate control beeping? I have no Idea why?

Naturally, I cleared all the codes and cleared them again to get rid of the P1642 -- and drove it for a 1/2 hour with no problems?

 

I get all sorts of lights and messages when my scanner is doing its thing.

Not all scanners like the jag communication protocols, try a local auto parts store scanner, see what it says. If it doesn't give the same errors, find a new scanner to use.

I think P1642 is fuel pump motor high current.

P1797 is Neutral Safety Switch malfunction which would constitute a performance related MIL. I've heard of a few of these switches fail. Mine has been acting up as a matter of fact, sometimes not starting in Park, and I have to wiggle the j-gate or drop to N to get it to start. Happens like once every 6 months or so.

Get yourself a copy of the JTIS, it has all DTC codes for your specific car. The scanner you're using isn't giving you the correct description.

 

I found this in my search also, ken@britishparts thinks the P1642 is a byproduce of the P1638... if you want more, do a forum search for P1368 and p1797.

This one also seems promising.

 

Thanks for the links -- my previous list and the list I just took from AllData show my listing for the codes to be correct? But they are all CAN links that can be the wires or any number of components??


Have not yet found any information on why I had the climate control panel tell me I had an error??

 

When the instrument cluster is not working properly, the climate control says error. The climate control uses the instrument cluster for vehicle speed via the CAN bus. I had the same problem when I tried to replace my burnt out bulbs with the wrong ones by accident behind my instrument cluster. The cluster shut the cluster down which caused 3 beeps and ER on the screen like you described. You can do diagnostics on the climate control system too.

 

Well that is interesting!

I have never had any of these components out of the car -- So my thinking is that it is unlikely that I have a connection problem behind the dash but who knows?

Do you know if it is possible to retrieve the codes from the Climate Control with out Jaguar specific tools??

 

You can check the error codes by doing this:
https://www.jaguarforums.com/forum/s...495#post199495

Hope this helps!

 

Thanks -- I probably should get the CD for all of this

 

I would sure try another brand of scanner (maybe Auto Enginuity?) before I tore into the CAN bus. Lots of folks have repoerted similiar codes, and few, if any have reported the root cause of whatever they were looking for to be the CAN bus. I could not be sure from your original post- What (besides the light) is your symptom? DO any of the ghost behaviors happen without the scanner connected?

 

The original "restricted performance" happened late one evening -- no CEL ever came on and no codes when I read them a few days later. It has never happened again except while I was playing around with the car for about 1/2 hour while the scanner was connected.

I have used three different code readers and often get the 1642 -- from reading up on it -- many people get this code.


From looking at the literature many items can give you the "RP" and they are often intermittent codes that are not stored??