UK Car Repair: Your answer for 1995 XJ6 that wont start, modern cars, complex control

Question
I seem to have the same problem.  Good battery, all lights come on, click only (not loud) at start attempt.  If I jump the wires and the solenoid works then what is the control system you refer to?

Answer
I don't know what answer you are referring to. Modern cars have complex control systems which need special computers to trouble shoot. That being said your problem sounds like it could be an alarm problem.  Try resetting the alarm by using the door key. Turn and hold the key to lock/unlock for about ten seconds, then turn the other way and do the same thing. If at first it doesn't help, try it again a few times.