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I'm suffering a intermittent fault with my gearbox,last year the transmission light came on and the gearbox seem to be stuck in 2nd gear, after turning the engine off and then back on a while later everything was ok no light or fault code on trip computer, now this weekend 3 months later I had the same problem again! While I was driving the orange transmission light came on and would not change up or down, I turned off engine waited a minute and restarted and all back to normal! Any ideas what's going on?
Any advice would be appreciated thanks Cliff

Sounds to me like possibly an alectrical glitch. Possibly a poor connection or a break in a wire?
I think your car is probably too old for plug in diagnostics of the OBD2 type but there may be a specialist with the older Jaguar- specific kind.
I'd usually say that with an auto gearbox fault a fluid and filter change is a good start as if can cure all sorts of funny symptoms.

Cliff,

First of all, when was the fluid and filter last changed? As David mentioned, an oil change on these ZF 4-speed boxes can cure a lot of problems. Secondly, see if you can have a look at the wiring switch on the side of the box. The wiring can become both brittle and oil-soakd on these models which can give rise to intermittent problems.

Good luck

Paul

Hi
Thanks for replys

Fluid and filter were changed about 2 years ago and only covered about 5000 Miles since, I'll check wiring at the weekend, some one mentioned a transmission relay which I should find in the boot, but cannot seem to find it,maybe that's the problem,it's not there!

Regards Cliff

I have exactly the same issue with my 1992 XJS 4.0. It seems to be getting worse with the orange light coming on more often though sometimes a stop, switch off and re-start cures the problem. I will look into a ATF fluid change first.

Bit of a long shot - but could it be an intermittent speed sensor issue? On my X300 Daimler Six I had issues after a non -jaguar garage replaced some wheel hubs. That was a mistake - they damaged one of the wheel speed sensors used by the ABS and ECU - caused the car to go into limp-home mode randomly until replaced. Corroded sensors can do the same. I appreciate that most XJ-S use a speed pick-up from the transmission or rear-diff - but was not sure about late XJS.