I have a 01 XJR with 93,000 miles. I get a gearbox fault light once in a while. It resets when I restart the car. The problem may happen a few times in one day or take a week to 10 days to happen. When the light is not on the car drives/shifts perfect. Very smooth. I could drive it 400 miles and no problem. When it does happen it takes place on very light acceleration from first to second. It feels like an aggressive shift and then the light comes on. Never had it happen with medium to strong acceleration. I did have the fluid changed recently after which the problem did not happen for a few weeks (which is not uncommon). I does not seem to be getting progressive, just once in a while. had the car for 6 years and only had the issue withing the last year. Took it to a shop to have the codes checked. P0715 (turbine speed sensor) and P1632 (can fault?) were the codes that were stored. He suggested to me to drive it until it gets worse as a rebuild would cost approx $4,000. I have never seen a transmission go bad in this way (great for a long while with an occasional issue). As I said earlier it drives perfect and shifts very smooth until the firm shift into second once in a while. No other issues. What could be the issue? Thanks for your help, Jerry

 

I think if I got codes intermittently that dealt with a particular part, I would just replace it after inspecting the connector pins and wires. Turbine speed sensor sounds sort of like an input shaft speed sensor on a 4r70w(what they should have put in these cars), so it may not be anything terribly serious. These are just some ideas. I am sure others will chime in shortly.

 

thanks for the advice man, iv taken it to another transmission shop and they said that all they could figure out was that there is a problem internally but they cannot figure out the problem until they take the transmission apart. I have a big problem tusting people with telling me the truth when it comes to things like this. so hopefully yall cant help point me in the right direction

 

Many transmission shops always say that. Once they have it apart, what can you do? Keep shopping for a better repair place.

 

What was done at the gearbox service? Did it get Mercedes ATF? I'd see a main dealer to scan the trans, or a good independent that has the same scanning system (Jaguar IDS/WDS) These boxes can tell all.
Has the battery been unplugged, or the electrical system had a reset? These gearboxes learn driving styles, I guess you know this already. Hesitant shifts mean low/high fluid levels in the trans, what's it like going into reverse?

 

I have the same problem on my 2000 XKR. There is a hard shft then the transmission fault message appears. The code is P0715. How did you fix the problem?

 

Has anyone fixed this fault????.........I've had p0715 and p1797 for months........sometimes its a pig to drive, sometimes its fine......strange thing is the dash goes mad for 5 seconds then returns to normal showing traction and stability faults...........!?!?!?

 

Looked up your codes on this site
Technical Resources OBD Error Codes

Possible causes of OBD code P0715
- Transmission speed sensor circuit is open or shorted. - Poor transmission speed sensor circuit connection - Faulty transmission speed sensor The Error code is generally activated on detection of the following conditions: Diagnostic Trouble Code (DTC) P0715 is detected when TCM or ECM does not receive the proper signal from the sensor.
They didn't have a code for P1797; came up with this for Hyundai
P1797
P or N Range Signal or Clutch Pedal Position Switch Open or Short.

I would check electrical connections first, on the transmission speed sensor, and the switches on the shift lever