Hi. Having exhausted all other (?) possibilities, it would appear that an intermittent electrical fault (switching the engine onto GetuHome power) on my 2000 Coupe is caused by a faulty gearbox ECU, or. possibly, in the gearbox itself.
I have been told that there are two solenoids in the gearbox ECU that are well-known to cause problems, and that this is a repairable fault? In essence it would seem that the ECU is more likely to be at fault than the box itself.
I would very much appreciate any comments or thoughts before I spend too much more on costly help!
Many thanks.

 

It would avoid confusion if you would refer to the TCU instead of ECU. There are likely to be fault codes stored, have you tried to read them? I assume you have checked that the battery is fully charged as that can cause some strange problems.
The thread below refers to the speed sensors in the transmission. It may be of some help:

https://www.jaguarforums.com/forum/x...rmation-78132/

 

Without the fault codes the cause is a crap shoot, may still be depending on the codes but you need to start with what is causing the car to go into reduced performance mode. The only time I got to reduced performance on a transmission fault was because I was taking corners too fast and the fluid level sensor tripped otherwise I got a blinking transmission light on the shifter. (That was a failed linier switch). But without the codes we can't help you very much.

 

UK Duke,
I had a problem a while back that I thought was the TCM.
It turned out to be the alternator was overcharging.
The voltage regulator is inside the alternator, so I replaced the whole thing and now the car runs great
Dave B.