What is the significance of a 'major defect' on a commercial vehicle's Schedule 1 inspection report under Saskatchewan enforcement rules?

1. The driver can drive for up to 48 hours before repairing it
2. The vehicle is immediately considered unsafe and must not be driven on any public road until the defect is repaired
3. The driver is fined but can complete their current trip
4. The carrier must replace the truck with a new model