(a) The Department is hereby authorized to determine those streets in the City of Los Angeles which have a grade exceeding three per cent and upon which a hazardous condition would be created unless unattended motor vehicles were parked by blocking the wheels of said vehicles by turning them against the curb, or by other means. When such determination has been made, the Department is hereby authorized and directed to cause appropriate signs to be posted and maintained on such streets. (Amended by Ord. No. 134,523, Eff. 7/17/67.)
(b) When signs are erected in places giving notice thereof, no person driving, or in control of, a motor vehicle shall permit it to stand on any street or highway unattended when upon any grade exceeding three per cent (3%) within any business or residence district without blocking the wheels of said vehicle by turning them against the curb, or by other means.