Actually if you close all doors and trunk, lock and unlock several times using key on drivers side lock. Make sure you hear chirp and door locks are activated up and down. Insert key in ignition and turn half way to auxiliary. Do not attempt to start engine dash lights should activate only. Wait 5-7 minutes. Alarm resets and engine starts right up.
I have a 1996 Jaguar XJS 2+2 Convertible. Car was on alarm with Red Console Light Flashing all normal. Then Remote Transmitter Lock/Unlock Device doesn't work. (Battery or?). Followed the Emergency Alarm Disarm Instructions in Jag Security System Manual. Full Alarm didn't go off, but Red Console Light is now "on" solid and the Car won't start. Car is somehow locked out from starting. I tried the above and it didn't work.