More and more frequently when I start the Jag, the starter is still turning after the engine fires. Is this the wire loom attached to the back of the lock? Trying to find any ignition lock or wire loom behind is impossible. Which leads to the next question, has anybody used a generic keyed ignition switch and made it work?

 

Ignition switch electrical section is now very common.

Wiring, NO, unless Freddy Fiddler has been in there Fiddling around.

Starter relay getting lazy, age related issue.

Access to the Ignition is very possible, fiddly, tight etc, but very doable.

Have a read of the attached.

 

denis,
easier place to start would be the ballast coil relay, starter solenoid gets it's power via a white/red wire form the relay, you could bench test the relay, or attach a test light with pos + probe on the white/yellow wire at the relay, if the white/yellow wire is still lighting up the test light after starting the car then it must be the ignition switch, which you could bypass the start function with a push button setup which i've done on cars in the past.