The family of a young father who was killed when an ice-affected teenager drove the car they were in off a cliff, believe that VicRoads are at fault, the Coroners Court was told on Tuesday.

The driver and three passengers, including Chris Reddin, 22, were killed when the 2001 silver Holden Commodore ploughed through a wire barrier on the Northern Highway in Pyalong, north of Melbourne, on January 28 last year.

The car was travelling north at 100km/h when the driver lost control, swerving across the highway and colliding with a wire barrier on the side of the road.

After leaving the highway the car skidded through vegetation and ploughed into a tree, where it was crushed into an L-shape.