Suddenly the car would not start. the fault code showed a
transmission control module (TCM) fault code.
After having done some research into the fault, I had
found it to be a characteristic fault with the x-types.
I recently purchased a new (31000 miles) TCM with the exact
same part numbers JATCO 1x43-72401-LC for a 3.0L
engine/trans. It appears that the part number suffix (LC)
can be different on this part so I was certain to get the
same as the original one that was removed.
well, the replacement was mounted, battery terminals
reconnected, attempted to start the engine, but no start/no
run. the fault code came back on.
any suggestions to what I can do next ? I also purchased a
new ECM just in case...(if I would have to replace it also)
does the computer need some sort of factory reset ? is it
something I can do myself ? if so, how ? as a last
question today, could the relays have been compromised ?

 

Goodride, welcome to the forums. Sounds like you have surfed around on the site a bit. As you are finding out their is a wealth of information on here and a lot of friendly helpful people. One thing we do require is that you stop by the New Member section and introduce yourself.

As for your issue. You said the code showed it to be a TCM issue. Can you post the code number? If your car was running perfectly fine and all of a sudden it will not start it could be something as simple as a weak battery. Our cars are know to throw a variety of codes because of that. Not unusual for a battery to just give it up, especially if you are in a cold climate.

If you can be more specific about the nature of your problem and post the code(s) you got I am sure there is someone on here that can help point you in the right direction.

 

Greeting Alfadude,
I had pulled the codes that are on the car. The codes are as follows in this order: P1643, P1632, P1637, P1644, and P1000. These do not seem to be generic codes but specific to Jaguar. The first three are both stored and pending. The battery is a good one with a voltage reading at rest of 13.4V.
The car just did not start. It was not parked after a "limp home mode" driving experience. all I had done was change a burned out fuse for my passenger side head lamp. Finding the fuse for the head lamp was a process of removing fuses and relays while the car ignition key was is ***'y 2 position (because the lights come on when starting the car and are on all the time while running. well, I found the fuse, replaced it, went to start the car, and no start. Message on the dashboard reading TCM fault.
I looked into the TCMs and found the part numbers must match. found a known "good" part with the exact same part number an 31,000 miles of use. It was then plugged in but no change to the message and still no start. That is where I stand now with the car...
(BTW, I take it you like alfa's, I have a GTV and spider in storage. Loved those cars !)

 

Goodride, sorry, but I am not technically savvy enough to help you get to the bottom of your issue, but now the you posted the codes and the circumstance when the issue popped up hopefully someone will be able to pinpoint if for you.

I can't say that I ever saw another thread on here with this issue. It just seems to me that if the car was running perfectly fine other than a headlight fuse and you replaced the fuse there shouldn't all of a suddeen make your ECM or TCM go bad. You might want to retrace all the things you removed and put back. Maybe something wasn't connected properly or completely. Wish I could help more.

And, yes, you are correct. Love Alfas. Had a '91 164S with factory recaros and have had a soft spot for them ever since. Where I take my car used to be an Alfa dealer and they always have a good number of them in there. Last week they had an absolutely mint blue mid-80s GTV with some modifications in for some work. The guy shipped it all the way from Pennsylvania to Wisconsin. Stunning car. If I had more space and money I would definitely buy one.

 

I spent a couple of momnths diagnosing my 2003 X-Type 3.0 in limp mode, went thru all of the typical stuff (TCM, ECM, etc). Eventually, a mechanic with access to all the Jag codes told me that the internal switch monitors well bad - which would require a new transmssion.

I had him change the AT fluid (which was black), and figured I'd drive the car while I attempted to look for a replacement transmission. After about 150 miles of driving, the care exited limp mode.

I'm convinced that these JATCO transmissions are VERY sensitive to cleanliness of transmission fluid - have put 5000 mi on it with no recuurance. The FIRST thing I would do is have the transmission fluid replaced.