How do you jump start Jag XJR?

To jump-start a Jaguar XJR, first ensure you have a working set of jumper cables and a functioning vehicle with a charged battery. Connect the red cable to the positive terminal of the dead battery and the other end to the positive terminal of the working battery. Then, connect the black cable to the negative terminal of the working battery and the other end to an unpainted metal surface on the engine block of the XJR to prevent sparks. Start the working vehicle and allow it to charge the dead battery for a few minutes before attempting to start the XJR.