Disconnecting the battery cables and going through the rectification process did not change the results. The "clunk" sound I hear seems to be in the vicinity of the starter, so that will be tomorrow's project. I hope I can access the starter from beneath the car after I jack it up about a foot or so and get some jack stands under the right side.

 

The other key that I have is an aftermarket key that worked when the locksmith cut it and programmed it. It does not start the car either.

 

No machinery or vehicle likes to sit for months. That is especially true for Jaguar.
What is - a "clunk" sound? Is that the starter solenoid? If so, check voltage to the starter on the starter side of the solenoid when energized.
SDD is a primarily a diagnostic tool, so yes, SDD can read diagnostic codes and reset or clear them.
If you are not familiar with SDD, look for a friend or shop who can help.
As MotorCarMan said, try your other key if you have one.
If you still suspect a security issue, and have no other options, you could try the rectification procedure:
Disconnect both battery cables and touch them solidly together for about 90 seconds.
Rectification depletes residual electrical charges and may calm a scrambled electronic brain.

Good luck.
Keep us posted on you progress/solution.

Bill[/QUOTE]
Problem solved. It turns out some critter chewed up the wire that connects the ignition to the solenoid. It was not an issue with the key or the security system. I reconnected the wire and I am now able to start the car and move on to the next dreaded project - the leaking valley hose under the supercharger. Thanks for the help and suggestions.

Steve

 

Steve first thank you so much for coming back to close the thread!
Sometimes it is simple if we can just find it. Good job and a free repair on a Jaguar is a real treat.
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