Hello Eric Lovins,
Your ignition switch goes directly to your BODY module and the engine control module... (with only a RELAY) in the mix...
for "starting purposes only"
My experience with Jaguars (magnificent vehicles) has
taught me to FIRST SUSPECT RELAYS... (easy access the switches (really hard to reach... If you plan on keeping the car
(mine being the last V12 Convertible they built)... I keep spare relays... HOWEVER...
Control of the running (or not running) seems to be the
Ignition control directly
from the steering column to the BCM.
Logically your Ignition switch (highly used & difficult to get to) should be most suspect... (there are also high risk of triggering logic circuits with RESULTING AIR BAG DEPLOYMENT (EXPLOSIVE FORCE
))... Use of care and full knowledge
is advised here...!!
I have the Factory Service Manuals
for MY '95 XJS...
They are impressively expensive... but WERE cheaper
(NEW, PAPER) than a single "visit" to one of my
neighborhood JAGUAR DEALERS...
(assuming all thing go well... they usually don't
While the Factory Service Manuals
are collectors items themselves you might remain in convinced of their inherent value... you can use the FREE data base at BBB Industries
website... (registration required)
(also see Jag Lovers site below (very bottom)).
I found no Technical Service Bulletins on your ignition lock
(a good thing)...
but in my car it would be very simple to eliminate DOWNSTREAM electronics... simply by removing the wire from the ignition (the engine should stop)
You can then confidently pursue that wire into your ignition lock
My vintage vehicle has no PATS (passive anti-theft system) keys... but I will assure your life will be happier if you make SURE you have all the required keys & fobs BEFORE you get into the lock.
More Information for STANDARD MOTOR PRODUCTS LX1013
More Information for STANDARD MOTOR PRODUCTS US1076
Start relay (always good to have SPARES)
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