What is causing my doors to not lock when using the key in the driver side door. on 1990 Volvo 240

when unlocking the doors,it seems a relay is constantly allowing the door mechinism to continue to engage to unlock.While driving a sound of moss code can be heard under the dash area.The doors cannot be locked as a unit, when turnig the key in the drivers door,only that door locks. If I lock the passenger doors,get out and lock the driver door with the key, all passenger doors unlock.

Asked by for the 1990 Volvo 240
Check the lock switch in the lf door. This can cause some of the symptoms you describe