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I get that Jaguar wouldn't want Kim Philby to have one but you'd think they'd be able to verify someone is a legit Jag mechanic. With none available it makes it impossible to fix the car. So their operating their business under the theory that their cars only last 10 or 15 years. Not very helpful.
As I said all the ECMs I'm finding only have the first part of the VCATS number. So I guess I have to find someone who has smuggled a diagnostic unit out of a dealership.
There many of us that found used WDS and IDS VCMs to load the Jaguar software onto still have them to fix old Jaguars.
There must be someone within 50 or 100 miles of you with a Jaguar diagnostic unit of some sort?
That's what the shop said. They also tried the "drive cycles" but no joy.
Is that the thing I would need to find out the VCATS number of a ECM?
I just talked to someone at Welsh Enterprises who supply older Jag parts. He said there may be an issue with the new downstream O2 sensors not talking to the old upstream ones. His suggestion was to buy a couple new upstream ones and plug them into the connectors and see if that clears the INC code. He said if the issue is the old ones aren't communicating with the new ones, just plugging the new upstream ones in will reset the monitor. It doesn't have to be inserted into the manifold. I'm not sure I believe that but I could order a pair and just plug them in and see what happens. If it doesn't clear the monitor I can return them.
Joe
Yes, as I understand it IDS (or whatever) is what's needed. The online kits come with that software and the special cable you need. If I keep my Jag I'll probably invest in one.
I'm skeptical about the O2 sensors communicating with one another. I really don't think these cars are that sophisticated. My understanding it that the upstream ones monitor the A/F ratio and communicate that to the ECU so that the ECU can adjust injector pulse width to keep the ratio around 14:1. The downstream are just there to make sure the cat is getting hot, i.e. still working. But I'm willing to be educated.
Hi Don,
I've been checking around and none of the dealerships near me have any of the "old" equipment around. I don't know what they do with it but the fact that they get rid of something like that tells me a lot about how the company stands behind, or should I say runs from, their products. I don't know how much floor space the equipment takes up but you'd think at least one dealership would have one. I mean this is the computer that controls everything on the car. The company that built it can't keep the equipment that is used to tell what the magical number is inside it. Geesh!!!
I think you will find it's the customers who have run away from Jaguar not the other way around. I absolutely guarantee that if your local Jaguar dealer still supported your car, you would be on here complaining about the $5,000 bill from the dealer to fix a $2,500 car.
The easiest way to get hold of the IDS software that you need is to buy the software and the cable on ebay and install it on your laptop. These cost less than an hour's worth of labour at a Jaguar dealer, which is another reason why Jaguar don't support these cars anymore. Only a lunatic would pay $150 an hour (or whatever the current rates are) for someone else to plug your car into a laptop and read the screen.
I just talked to someone at Welsh Enterprises who supply older Jag parts. He said there may be an issue with the new downstream O2 sensors not talking to the old upstream ones. His suggestion was to buy a couple new upstream ones and plug them into the connectors and see if that clears the INC code. He said if the issue is the old ones aren't communicating with the new ones, just plugging the new upstream ones in will reset the monitor. It doesn't have to be inserted into the manifold. I'm not sure I believe that but I could order a pair and just plug them in and see what happens. If it doesn't clear the monitor I can return them.
Joe, I'm sorry to say that someone at Welsh Enterprises doesn't have a clue what he or she is talking about. Jaguar uses the term Engine Control Module (ECM) to describe the main engine computer to distinguish it from other Electronic Control Units (ECUs) and from Powertrain Control Modules (PCMs) which control both an engine and transmission and sometimes differentials and a transfer case. The ECM monitors the signals of the upstream and downstream HO2S's independently. The sensors are only output devices and have no capacity for receiving or interpreting information from other sensors. And connecting an oxygen sensor's electrical connector without mounting the sensor tip in the flow of exhaust gasses will trigger multiple diagnostic trouble codes (DTCs) not related to your current issue.
A good independent shop that has Jaguar WDS or IDS (or SDD versions up to at least 131, which will revert to IDS when connected to an X100) should be able to help with your VCATS identification.
Another idea is to see if there's a good European shop with a high end diagnostic tool like an Autel, Launch, AutoLogic, etc. and knows how to monitor and interpret Live Data. It is possible that there are clues to your problem in the sensor signals that could be understood by someone with the right knowledge and experience.
I can't remember - have you found any U-prefix codes for communication problems between modules?
My 2001 XK8 is throwing these codes. In reading the threads on here and other Jaguar sites the issue seems to be a problem with the communication between the various computer modules. I've removed all the plugs and cleaned the contacts. That did not do anything. In looking into other issues I'm having, specifically the inability of the car to reset the CAT monitor, I opened the compartment that holds the ECM and TCM. Both units appear to have been replaced at some point in the car's 64,000 miles. The TCM has a label on it that has the incorrect VCATS number on it. The sticker in my trunk indicates that the TCM should have a VCATS that ends in the suffix 003 but the label on the unit ends in 002.
I've been looking on ebay and other locations and can purchase another TCM with the correct VCATS number. Could this be the issue that is causing the 1797 and 1799 codes? Can my TCM be "reprogrammed" with the correct VCATS information?
Joe,
If that barcode section is the software revision, then the TCM came out of the factory with version 002. However, it is possible that it has been updated at some point in the past.
AFAIK, the only way you can confirm this (and the revision of the ECM you have) is via Jaguar's proprietary diagnostics:- unless one of the modern readers has that capability.
Here are the definitions from the 5HP24 DTC list for those two codes:
As Chirpy noted in your other thread, P1797 should drop the transmission into limp-home mode. Both of these are CAN-related, so you may have an issue there. Did you include the ABS module connections in your checks?
I have merged your most recent thread with your previously most recent thread so that all posts related to this issue will remain together and other members can follow the full story. Please do not start any new threads on this same issue. It only creates confusion and duplicated effort on the parts of those who want to respond.
Thank you. I wasn't sure if I should put the transmission issue into a new thread since it wasn't related to the CAT monitor issue, but if that's where it should go, no problem here. I just really want to get this thing running.
Thank you. I wasn't sure if I should put the transmission issue into a new thread since it wasn't related to the CAT monitor issue, but if that's where it should go, no problem here. I just really want to get this thing running.
Joe
This thread started out with the transmission codes then morphed into the CAT monitor issue, so let's just keep it all together. You've given the transmission codes a good bump, so maybe someone else will have some ideas. You have established that the replaced TCM has the incorrect 002 VCATS firmware version. According to the VCATS label in your car, it should be version 003. We have to suspect that the replaced ECM may likewise have the incorrect firmware.
Both of these are CAN-related, so you may have an issue there. Did you include the ABS module connections in your checks?
If the CAN wasn't working I'm sure there would be more than just these two fault codes? Fmertz suggested measuring the resistance of the CAN bus back in post 6. I think I would check that and if ok move on. OP knows the TCM module is incorrect. Someone swapped it at some point for some unknown reason. At the very least get the right module/version as its impossible to say what errors having different versions of the firmware will cause.
I still think it's entirely possible the readiness monitors will set if the OP just drives the car.
If the CAN wasn't working I'm sure there would be more than just these two fault codes?
Agreed, if it was a hard fault - I'm wondering why there's no CEL? Identify or replace both modules in case the monitors won't set because there are active codes.
If the CAN wasn't working I'm sure there would be more than just these two fault codes? Fmertz suggested measuring the resistance of the CAN bus back in post 6. I think I would check that and if ok move on. OP knows the TCM module is incorrect. Someone swapped it at some point for some unknown reason. At the very least get the right module/version as its impossible to say what errors having different versions of the firmware will cause.
I still think it's entirely possible the readiness monitors will set if the OP just drives the car.
I have checked the resistance across the contacts and it is what it is supposed to be.
Agreed, if it was a hard fault - I'm wondering why there's no CEL? Identify or replace both modules in case the monitors won't set because there are active codes.
CEL ?
I think I've located a shop down in South Orange County that can check the modules and if necessary reprogram them with the correct VCATS. I've also located a TCM with the correct VCATS number. It's fairly inexpensive so I thought I'd pick it up just to have it. At this point I have no idea who did any of the work on this car or what they did but judging by the fact that they installed the wrong TCM at some point who knows what else they've screwed up on this thing.
One of the members suggested a independent Jaguar shop in Orange County so I called them. The owner suggested replacing the upstream O2 sensors as the next step and see if that made a difference. At $400 each I'm not to inclined to replace them without knowing it's going to work. He also said that the CAT monitors on these cars are notorious for being a problem to reset. He also suggested just driving it more to see if it resets. My problem is the registration is expired at this point and I can't get it registered without the monitor resetting. Talk about your Catch 22.
Thank you Michael. If the other TCM has the correct VCATS number is there any "programming" that is needed or should I just be able to unplug the old one and plug in the new one? (after disconnecting the battery).
Joe
I joined JCNA and the local affiliate yesterday. Today I spoke to the president of the Los Angeles club. He was able to put me in touch with a nearby shop that has the equipment to check out the ECM and TCM and make sure everything matches. I know the TCM doesn't so I've ordered another one with the correct VCATS. That should come in while we're on a little vacation. I spoke with JP at JP's European Auto, Inc. It's relatively close to me so I'll be taking the car in when we get back. With any luck I'll get the car down there without any problems regarding the expired registration.
