Cadillac Repair: 1999 Cadillac Deville Alarm, cadillac deville, pin switch

Question
My alarm will go off for no apparent reason and I have even had my radio come on will  all doors locked. To avoid the security system from working I now lock my car by key, turning the system off. What might  be causing the alarm to activate? The radio to activate?

Answer
Hi Tom,

I am an expert in the ignition anti-theft systems. Factory alarms in many cases require hands on diagnoses in most cases, but I will throw you some thoughts. Please keep in mind that I have not worked on the factory alarms for many years, but Cadillacs were common to me.
What throws me off is the radio going on with the doors locked. The radio going on may be a separate problem with the retained power with the doors closed. To my knowledge, the radio is not even wired to the factory alarm.
A dome light circuit problem can cause the problem. A door pin switch could cause falsing. Some GMs ran shock (impact) sensors in them as well and that could be too sensitive. The sensor was commonly found in the trunk. It could be a bad module as well.
I wish I could assist you better, but without seeing exactly what is happening to the vehicle and how often this problem happens, a forum like this is just good for suggestions.

Thanks, for the question.

Rob