Yes, theft deterrent systems will blink the marker lights when activated. Did you reset the air bag light as alaxfire suggested?? Did you swap the locking pump or check for water in the rear?
Has the car any Diagnostic Trouble Codes?
Does your siren activate when you push the red button on the key fob? No, you have a bad battery for the theft deterrent system (common problem as the cars age) Most people just unplug the siren and ignore it. If it is unplugged it will not effect anything other than no siren. The rest of the system will operate okay. Not sure if a corroded board in the siren could effect it activating your parking and marker lights, but that seems to be a possibility.
Where are you located? I am not far from Enterprise.