CONCERN: Customer reports that the food in the refrigerator section is too cold, the water sometimes does not dispense, there was a loud knocking noise that went away, and the fresh food door is not closing on its own. DIAGNOSTIC AND CAUSE: Inspected evaporator fan motor operation, evaporator fan operation is normal at this time. Inspect air return for restrictions, no restrictions at this time. Inspected the damper door assembly operation, found refrigerator damper assembly failed and is not closing. Also found fresh food door cams worn. CORRECTION: Replaced refrigerator damper assembly, installed new door cams, and tested. Operation now normal.