2000 XKR. Just driving along easy all of a sudden the transmission will thump into 3rd gear and the message "transmission fault" comes up on the information center. The code I retrieve is P0715 turbine speed sensor. I erased the code and everything was fine for a while but I am having the problem alot now. It appears that others have had this problem but most threads do not say how the problem was fixed. Any informations about this problem would be appreciated.

 

Had the same problem about a month ago. First, replace solenoids in tranny, faults returned. Then replaced trany wiring harness, faults never left. Finally, replaced shifter box and solenoids in shifter, and the faults came back twice the first day, but have not reappeared in the past three weeks. Hopefully, I will not have another episode.

 

tberg, Thanks for posting! This gives me more to check out.

 

The turbine speed sensor is a hall effect sensor mounted to the mechatronics unit inside the tranny. If you can get the part and remove the mechatronics unit, it is easy to get to. Before doing this, I would pull the electronics connector on the tranny and clean it thoroughly and see if its just a bad connection there. I would also trace the main tranny wiring harness to look for damage or bad connections to the TCM module. Be sure all the conections are good before replacing the sensor. Check for it because some parts like this are not available through Jag. You can buy a new mechatronics unit from thectsc for about $1500, check to be sure the ISS is on it though.

 

I meant to mention, the ISS could just be coated with metalic particles, casuing it to malfunction as it is a magnetic sensor. It could be just that the oil is contaminated and has coated the mechatronics unit with conductive metal. If you pull the unit out and clean it with electronics cleaner, that may fix it. It is easy to get this unit out, just pull the pan and let the bolts loose, it will come out. Be sure to get the dignostics instructions though, for the small details.

 

The mechatronic units in these trans, that holds the ISS, with a lot of miles and no fluid changes become gray with ultrafine metallic particles, which can cause failures. This is another reason why these units need oil and filter changes every 60K miles! Most cases show that the TCM inside the tranny is a good idea-----unless the fluid bcomes metallic!

 

I keep thinking of things I wanted to say! You might wonder where all this metal comes from. Each clutch (A-E) pack has a series of alternating metal and fiber disks that when pressed together by hydraulic pistons, cause the tranny to function. They are exactly like a motorcycle wet clutch. When these things spin unlocked and then are activated, the friction disks create ultrafine metallic dust from the steel disks, putting the metal in suspension in the super fluid, where it eventually settles out on everything in there.

 

Oldmots, Thanks for all the help! I began my search for a manual for working on this transmission but the Jaguar manual (JTIS) has very little information. Should I search Mercedes or do you know where I can find online?

 

I just realized that you have the Mercedes W5A580 tranny in your 4.0 XKR, not the ZF unit. I have given you information for the ZF in error. I apologize for wasting your time.
There is not much discussion of this tranny on the site, probably due to limited numbers of units out there or good construction. Just guessing, most trannys use an external ISS on them. Look into it, you may be able to get to it from the outside. The ZF 6hp26 has its electronics inside the tranny.

 

Take a look here:
P0715 (input Turbine/speed sensor malfunction) - 2001 Mercedes-Benz C240