12. OPERATION WARNING 12.7 SWINGING When operating the swing, check that the area around the ma- chine is safe. 1. Before operating the swing, turn swing lock switch a OFF (CANCELLED). NOTICE Check that swing lock lamp b goes out at the same time. 2. Operate the left work equipment control lever c to swing the upper structure. 3. When not operating the swing, turn the swing lock switch a ON (ACTUATED). PC450-ENG 2-63