1996 Chevy Tahoe Power Door Locks

Electrical problem
1996 Chevy Tahoe V8 Four Wheel Drive Automatic 280K miles

Truck sat for three months while doing repairs (tune-up, water pump, radiator, thermostat, fuel pump, brakes, rotors, end frontend work). Went to drive truck and the doors locks started to lock and unlock by themselves. I locked the doors, returned to truck about 15 min later and doors were opened. Locked doors again, next morning doors were open. Doors would not lock/unlock at first but started to lock/unlock intermittently whenever I pressed the door lock/unlock button. Now doors will not lock or unlock at all. However, you can hear the relay switch clicking when you push the dook lock button.