Backed out this morning and realised I had no stereo or back-up sensors on my 2008 XKR. Sure enough the whole nav system was locked up with the Jaguar logo showing but fainter than normal. I remembered that I had been messing with the Bluetooth in the garage on Tuesday night, so maybe I lef tit in Convenience mode and drained the battery. Clearly a reset was needed.

At work I disconnected the battery -ve for five+ minutes, reconnected, waited another 5 and then started the car. The nav system came straight up in a way that looked quicker than before. Hmm, my imagination? The only other thing I noticed in this process is that the -ve terminal was not all that tight.

Drove the car home and noticed it seemed very lively with better shifts when cold. WTH? Took it out again tonight where I had to climb some hills. No doubt about it, the engine sounds sharper and pulls better.

Is this because the adaptive map is relearning my driving habits and the gas I use? The XKR now behaves like a car I used to have that the previous owner had run on Regular when it needed Premium. I switched gas and reset the ECU and the car got much livelier. I now wonder if the previous owner of my XKR got cheap and ran it on Regular. Failing that, does the adaptive map just get clogged up and needs clearing from time to time?

I now wonder if the battery -ve was not tight enough, causing some oddities with sensors and charging. I also wonder if the nav system has some memory that needs purging occasionally. It now comes up very quickly and the Bluetooth connects to my phone in an instant. I have not tried the nav function yet.

One thing is different. When I shut the car off the nav screen goes dark straightaway. It used to hang around showing the Jag icon. I shall have to see if there is a menu item that got reset or was it wrong before. I had to have two goes at resetting the windows. It did not take on the driver's side as the auto up would not work. It is all good now.