Ericsson had set the 14th-fastest time of a tricky session as drivers struggling with wind across the Circuit Paul Ricard.
But with just three minutes remaining in FP1, Ericsson lost control at high speed and careered across the run-off area before hitting the tyre barriers.
The rear section of the car almost immediately caught fire – although Ericsson did not immediately realise that there were flames licking up the barrier.
“I lost my mirrors so I didn’t see the fire,” Ericsson said afterwards, assuring fans that he had suffered no injuries in the incident.
Ericsson was sent a panicked radio message by his team – “Out of the car, quick!” – before jumping out of the seat.
But the Swedish driver, who has been with Sauber since the beginning of the 2015 season, was not immediately greeted by track marshals.
Eventually, a number of Paul Ricard officials arrived on the scene with fire extinguishers and were able to get the blaze under control relatively quickly.
However, the fire still managed to burn away the entirety of the engine cover on the right hand side in worryingly quick time.
More to follow.