I have driven my Jaguar XKR supercharged for 10 years without any problems. A few days ago, after a long trip, I left the car in a sunny place and the fan was still running after I switched the engine off. A few hours later I started the car again but it would not let me shift gears. I unscrewed the screw located on the gearbox panel and I push the pin down to release the gearshift. (automatic J) It worked fine. No warning lights except "the engine is in safety mode" message, which came on intermittently. Could excessive heat be the reason? Why would it block the gearbox? The engine starts fine every time. The warning message has now disappeared I drove the car home. What are the reasons for the car to block gearshifting?

 

Others may well have more specific advice but how old is battery. Usually a good place to start with these cars.

 

You need to help us help you by specifying the model year. For the earlier 4.0 cars, the inability to pull out of "P" points to the brake switch not being functional. They are made of small 2 small electronics-type switches, and are known to become unreliable over time. I believe that in the earlier 4.0 cars, the engine goes into safe mode when the switches go bad.

They are a bit pricey to get, and somewhat of a pain to put back, but within reach of a determined home mechanic. There are several threads on this forum detailing several techniques from replacements to repair.

Best of luck, keep us posted.

 

It is a 1999 Jaguar XKR Supercharged, 390BHP, The battery is not more than 2 years old. Are there any other batteries apart from the main one? The car is now working perfectly fine. I do not think that the break switch is faulty. Since the cooling fan was still running after the engine was turned off, I wonder if excessive heat has anything to do with it? I have checked all fluids, there are no warning lights. The car is regularly serviced. There must have been a reason why the car deactivated the shift lever in order to avoid damage to the engine perhaps? Is it safe to unscrew the bolt on the gearbox and reset the safety pin blocking the shift lever? If it happens again, this is the only way I can move the car.

 

Others may disagree, but I wouldn't start any surgery yet. The fan running on is not a fault, the ECU will keep it going until the temperature has dropped below a certain point, and after a long run, that's normal.
No - there's only one battery but, on an 18 year-old car, there may be a slightly loose or slightly corroded connector amongst the hundreds or so on the car.

Using the "manual release" for the shift lever won't do any damage whatsoever - that's why it is there !!
If it happens again, a "fault code" may be stored in the engine's computer (ECU). Get that read as it will help to narrow down the problem.

 

You should keep it (high) on your list.

The brake switch lets the computer know your foot is on the brake so it can let you move away from (P)ark. This switch is actually 2 switches activated together, one is normally open, the other one normally closed. If the computer see they are no "opposite", a fault is detected. These typically do not have a clean fail. They work intermittently for a while. Next time this happens, try and activate the brake pedal on and off a few times to see if the switch starts to work again.

Best of luck, keep us posted.

 

Have you checked the coolant level?