Hi all , my 1996 xjr has been draining it's battery over a three day period. I've noticed the radio doesn't turn off when I turn off their ignition switch. I swapped an ignition switch with a parts car I have and didn't get them results I was hoping for. Any thoughts as where to begin my search. I've not noticed any tinkering done to their car by previous owners , all these harnesses seem intact .
As always any help is greatly appreciated..
​​​​​​​Thanks

 

The radio staying on is a clue. By any chance, have you or any previous owners modified the radio and sound system, like adding an after-market player, equalizer, etc.? I have a bad experience of the electronics on my HiFi panel and sub-woofer of my Mercedes going south one day and the first symptom was the radio and the music player becoming mute. At the time I thought that the battery was getting too old to drive the equalizer etc. which drew power directly from the battery. I replaced the battery and found a blown fuse. The fuse kept blowing until I fully disconnected the whole thing, and things returned to normal. Try tracing the radio group of wiring and see what wire or fuse might have gone wrong.