Have had trouble starting my 1996 XJS AJ16 4 litre in Park and always start it in Neutral, will rebuild or replace rotary switch on tranny this winter, but today transmission stuck in Park. I can't get out of Park, is this the rotary switch or something else?
Snowball

 

Can't speak to the starting problem, but you can get out of park by removing the gearshift cover (two small screws) and carefully setting the brush aside, and then -- to the left of the shifter is a hole that you can put down a small flat screwdriver or the gas cap key.
At least that's what I did and the problem has not returned.

 

barmorehome is correct about using the lock bypass to get your car out of Park, but that won't solve the problem. I also had the same issue, and the problem lies in the Brake Light Switch.
I've attached a file which may be of some help.

 

Just an update. Had it for a good run before this happen, after checking every fuse and looking at relays, low low battery. Thanks for the help.
Snowball

 

Mine did that too. I removed the gadget at the gear shift so it couldn't ever do that again.
RagJag