I've got a 2003 STR that spent a year in the mechanic shop as they tried to rebuild the transmission and get it running again. They rebuilt the clutches, but the TCM is throwing codes, making the transmission jump when the car is on. We tried replacing the shifter and twice had the TCM serviced to be reprogrammed, but nothing worked. $3k worth of work later, the car still isn't drivable. Any advice on what to do next? Is it a lost cause? Should I try to sell it as is, and for how much, if so? Any advice from someone who's got experience with this would be greatly appreciated!

 

We need the codes as it can be a lot of different things?
The 6 speed ZF is a very common and well known transmission. Does this shop have any experience with them?
They have been out for over 20 years now and have been used in dozens of different car brands.

You might see if you can find a ZF shop? Maybe try a different transmission?
.
.
.

 

Thanks for the quick reply. I don't have the codes, but they said the TCM went bad. We tried finding another TCM that would fit the transmission but couldn't. Tried reprogramming and servicing the TCM, no luck. Is it possible to buy a transmission that fits the car and just bypass the TCM entirely, as trans replacement would include a functioning TCM. At this point, I'm not sure the car is worth the extra money to fix it. Seem like a skilled mechanic may be able to fix it. IDK

 

Good questions and they are above my knowledge! But no the TCM can't be bypassed.
Does your shop have and use SDD? This is the Jaguar factory diagnostic software.
I refer people to the best ZF supplier I know and have used several times before. Don't know what your problem is but the TCM is usually reprogrammed? But I am sure they can fail too?
The CTSC - ZF Parts

Might be worth talking to them? I had a 2005 STR so real similar to yours.
Without codes we can be of little help?
I have attached some ZF documentation for background.

I just found this and I get confused by terminology but I think what ZF calls the Mechatronic unit is what others call the TCM?
I also forgot these have a common problem with the sealing sleeve leaking transmission fluid. The leak allows transmission fluid to migrate thru the sleeve and into the wire harness causing electrical problems. This might be what's happening with yours?

Cheap part at around $15 but the pan has to be dropped to replace it. Make sure the sleeve is FULLY seated BEFORE reinstalling the pan and filling with fluid.
Attached are instructions on changing the Mechatronic units.

Again if possible this is all a guess without codes and more information?
.
.
.

 

A year!!

OMG. Change mech!!

 

Not sure if this is your problem but after changing the fluid on my 06 STR and resetting the TCM I needed to drive it real easy for about 8 miles before the transmission started shifting right. Before that 8 miles it was acting possessed

 

It's relearning how things shift / fluid moves / fluid pressure changes / etc.

 

Indeed there is a procedure for the adaptations reset and relearn somewhere here in the forum and I believe I even have it saved but it’s quite important to do so after having the transmission serviced.

 

The best method to reset the adaptations involves two people and the Jaguar SDD/IDS software...

 

Yes I agree with S-Type Owner Jaguar recommends using SDD/IDS to do this.
Attached is the TSB but without hooking your car up to a working SDD system I don't know how much use this will be to you?

I would agree with JagV8 it's time to take the car to a different shop.
Try to find one the has a working SDD system as that's what your car needs.

But without codes we are lost?
Can you post any?
.
.
.

 

You can get your TCM un-bricked if you send it to Cambo in aus .
i've had to do two now .
. some of the early s-types had one programming wire missing from the trans loom .
which bricks the tcm when you do an adaptions reset . ask me how i know .twice two seperate cars
an 02 and an 03 .
Cambo can bench ref-lash the TCM and send it back to you .
the TCM can take weeks to smooth out whilst re-learning adaptions .
but
if it jumps into gear hard , the trans is in limp mode . you'l need to fix that first with the re-flash

 

Great info Datsports!
I hope Cambo still fixes this too.
.
.
.

 

Yes I believe so I forgot to put a link
. https://oldjaguar.com/about/