How to reset security system? on 1996 Buick Regal

The security light stays on all the time. Lately the horn has been going off whenever it wants to. Put key in and sometimes it goes off. Had to unplug the horn.

Asked by for the 1996 Buick Regal
Try using your spare key and see if the problem goes away ( a "bad" key can be a possible cause). If this doesn't work you would have to start diagnosing the system from scratch. I just looked on Alldata they have pretty comprehensive instructions, (look under Diagnosis and Repair then Accessories and optional equipment, then anti theft/alarm. Alldata is very easy to navigate
The information is year make and model specific, covering repair procedures, torque specifications, fluid capacities and specifications, service bulletins, component locations, wiring diagrams ect...
1 more answer
the horn pad has an issue for the horn part. have it checked as it may need a new pad.

the security issue may be just the key. try another key to see. if not, then the lock cylinder may be bad. have it checked at a shop to confirm and get a bid.