Shortly after the driver pulled over to the side of the road the Vauxhall Zafira was engulfed in flames and its windows shattered, showering the road with glass.
Islander Russell Osmand, a car salesman, stopped to help when he saw smoke coming from the front of the car when he drove by on Route de la Haule at about 4 pm.
Mr Osmand has now issued a warning for Zafira owners to contact Vauxhall, as there have been reports of similar fires earlier this year in the UK.
In October the company said it was trying to contact hundreds of thousands of British drivers over fears that the Zafira B was faulty.
Following an investigation Vauxhall issued a recall of 220,000 Zafira B models after around 200 fires had been reported.
