Traffic backed up on the busy road, which serves as the main corridor linking Phuket International Airport with the rest of the island, just after 12:40pm as police, rescue workers and firefighters arrived to battle the blaze.
The car was pulled over into the emergency lane just south of the intersection to turn-off to go to Nai Thon and Nai Yang beaches (Route 4031).
The firefighters from Thepkrasattri Municipality managed to douse the blaze after about 15 minutes, but not before the flames had gutted the entire vehicle.
Capt Chatree Chuwichian of the Thalang Police said the driver, Weeraya Thitiworana, 34, escaped unharmed.
Ms Weeraya was travelling to Phuket from Takua Pa District in Phang Nga, just north of the island, Capt Chatree explained.
“She said she saw flames coming from under the bonnet and pulled over as quickly as she could. She got out of the vehicle and called for help as soon as possible,” he said.
“We believe the fire was started by some electrical short, but we have yet to confirm the exact cause,” Capt Chatree added.
The Range Rover SUV was insured for B1.7 million, he noted.