If you think your car is about to stop, try to find a safe place to pull over. On a dual carriageway or on a motorway, this could be a layby or hard shoulder.
If the car grinds to a halt before you reach a safe place, try to bring it to a halt as far away from the main flow of traffic as possible. Pull off the road if you can on an A or B road and pull on to the hard shoulder on a motorway. Turn your tyres to the left so the car can't roll in to the passing traffic.
If you're on a smart motorway and there's no hard shoulder, stop in the emergency refuge area or pull over off the road if you can.
If you stop on the carriageway and you can't move the car off the road, put your hazard lights on straightaway, stay in the car with your seatbelt on and call 999.
Never try to mend the car at the side of the road. Call your breakdown service and leave it to the professionals.
Put on the car's hazard lights, and its side lights if conditions are gloomy. If you're not in a safe place, such as a layby or service station, you'll need to leave the car.
On a busy road, in poor weather and in the dark it's difficult for other drivers to see you when you get out of the car, so be sure to wear a hi-vis jacket.
If you have a warning triangle, place it at least 45m behind your car. This gives other drivers a heads up that there's a hazard ahead. Don't place a warning triangle on the motorway – it's too dangerous.
When you stop on a motorway hard shoulder, everyone will need to get out of the car and stand behind the safety barrier, well away from the broken down car. Ideally, they should all be wearing hi-vis jackets.