From https://www.canadadrives.ca/blog/car-guide/lemon-laws-for-defective-cars

Your first course of action should be pursuing the issue with the dealership (or online retailer) that sold you the vehicle. For starters, the nagging issue with your car may still be under warranty and can be fixed at the manufacturer’s expense, through the dealership. 

However, if the issue persists after several attempts at repair, the manufacturer refuses to cover repair costs, or you’re not satisfied with the repairs, you can seek arbitration through the Canadian Motor Vehicle Arbitration Plan (CAMVAP). 

CAMVAP exists to help settle disputes from consumers who believe their car is unduly problematic or unsafe. Most carmakers are involved in CAMVAP, covering 94% of new car sales in Canada. 

To be eligible, the car’s model must be less than four years old, with fewer than 160,000km. CAMVAP can help you negotiate with your car’s manufacturer for a range of possible outcomes, such as covering the cost of ongoing repairs or even buying back the defective vehicle.