I have a '00 XJ8 3.2, and got a trouble in yesterday.

After the trouble happend, wheels can not be driven by transmission if I put shift lever to "D" position. That is to say, engine speed becomes high with throttle pedal down, but the car does not move. No error message at that time yet. Then, with more throttle pedal down, the transmission suddenly connect engine to wheels with shock. The engine speed is around 3,000rpm at that time, also an error message "Transmission Fault" is displayed in console.

After that, I can still drive the car with 4th gear only, without lockup. Reverse gear has no problem.

Anyone experienced/knew/heared such problem? Please help.