I was working on the wife's gear shift because it has been stiff to select gears. Lubed the inner works and it feels better. Noticed the two micro-switches on the right hand side and the rearmost one is missing the tiny metal finger that presses on the actuator button. What does this switch do and is this a major problem?

 

not sure what you mean by the 'inner works'? I had the same issue and it was the cable ball joint on the selector arm on the gear box, it was seized solid

 

There was a resent tread on this missing finger if you go back 5 or so pages

 

It has been a number of years since I last worked on the J-Gate. If I remember correctly the the rear micro-switch tells the transmission control module you are in manual mode and allows you to control shift.
To be sure put the J-Gate shifter in the #2 or #3 position and go for a spin. Does the trans shift normally up thru the gears? If so the switch is for manual control.
Unfortunately as far as I know the switch can't be purchased you have to buy the cam plate as an assembly.

 

Note the VIN #

https://www.jaguarclassicparts.com/u...trol-automatic

 

Here is the recent thread on the topic that was mentioned above. It might give you some ideas:

https://www.jaguarforums.com/forum/x...switch-195836/

 

The D4 switch rides on the cam plate and has a white plastic roller. It is located at the front of the selector lever housing.

The other two switches on the plate on the right side are the PARK and NEUTRAL switches.

bob

 

Oh my, it seems I forgot to update the results to my own thread. The microswitch tab dsnyder586 sent me fit like a glove and have worked like a charm. My problems were fixed.

 

Thanks to Motorcarman. I checked all functions on a test drive and it shifts fine in all gates but the starter does not work if in neutral. I can live with that!