Albert Barnes Commentary Judges 4:15

"And Jehovah discomfited Sisera, and all his chariots, and all his host, with the edge of the sword before Barak; and Sisera alighted from his chariot, and fled away on his feet." — Judges 4:15 (ASV)

Lighted down off his chariot - Probably his chariot stuck in the morass (see the note at Judges 4:7); or he might have left his chariot in order to mislead his pursuers, and in hope of gaining a place of safety while they were following the track of the chariot-wheels and the main body of the army.