I WAS DRIVING DOWN THE HIGHWAY WHEN THE VEHICLE WAS IDLING AT A STOP LIGHT BEHIND SEVERAL OTHER VEHICLES. I WAS FEELING HOT SO I TURNED OFF THE HEATER AND DIRECTLY AFTER SMOKE FLOODED THE CABIN. WHEN THE LIGHT TURNED GREEN, I PROCEEDED FORWARD AS FAST AS POSSIBLE TO THE PARKING LOT AND THE VEHICLE CAUGHT FIRE FROM THE PASSENGER SIDE WHERE THE COOLING SYSTEM RESERVOIR WAS NEAR THE UPPER TOP CORNER OF THE PASSENGER SIDE OF THE VEHICLE. THE VEHICLE WAS OFF AND IT SOUNDED LIKE THE FANS/ENGINE WAS STILL RUNNING DESPITE THE KEY BEING REMOVED.