Not sure of CURRENT Ontario regs, but it used to be you had head and tail lamps,perscribed direction and brake indicators, perscribed "blink markers" and then all the rest. The head and tail lamps, as well as the perscribed directional and indicator lights, and the perscribed blink markers MUST work. Any non perscribed lighting, being optional, did NOT have to work. However, to avoid any hassle, if any were out it was usually best to just switch them off and not draw any attention.
The regulations read something like "All perscribed lighting". If it read "all installed lighting" you'd be in trouble.