It shall be unlawful for the driver of any vehicle to disobey the instructions of any traffic sign or signal placed in view by authority of the mayor and by and with the advice and consent of the council, or in accordance with the laws of the state, excepting on direction of a police officer. All signs and signals established by direction of the governing body shall conform to the Illinois state "Manual Of Uniform Traffic Control Devices For Streets And Highways". (1963 Code)