Cadillac Repair: Cadillac Security System, 1993 cadillac seville, cadillac seville

Question
Hello,
A couple of weeks ago I locked the keys in my 1993 Cadillac Seville.  When
the locksmith opened the door, the security system went off.  the only way
that I could stop it was to unplug all 4 of the horns.  the car runs fine, the
only problem now is I do not have horns, and the lights will not go off.  I have
to remove the negative battery terminal so my battery is not drained.  Do you
have any suggestions on how to get my car back to normal?

Thanks,
Matt

Answer
Sounds like you may have more problems than you think but let's try the easy thing first. It's possible the problem is the relay. Locate the horn relay. I believe you'll find it in the underhood electrical panel. Replace it with a known good one. Check the adjacent ones to see if any of them are the same number relay, if so try it.