A 54-year-old woman has died in a collision between a car and a road train at the intersection of the Stuart Highway and Olympic Dam Highway at Pimba on Thursday afternoon.

Emergency services were called to the scene just before 12:30pm on July 3, following reports of a serious crash involving a Toyota sedan and a road train.

Tragically, the driver of the sedan died at the scene. Her passenger, a 74-year-old man, sustained injuries and was taken to hospital for treatment. The driver of the road train was not physically injured and underwent mandatory drug and alcohol testing.

The highway remains closed to heavy vehicles while Major Crash Investigators work to determine the circumstances of the incident. Authorities are urging heavy vehicle drivers to wait at the nearest rest area until the road reopens.

Police are appealing to anyone who witnessed the crash or may have dashcam footage to contact Crime Stoppers on 1800 333 000.

The woman's death marks the 40th life lost on South Australian roads so far this year.