Thirty-four-year-old Tequila Isaacson was driving through Snoqualmie Pass in Washington state on Sunday when she saw a pickup truck in flames at a rest area.
Isaacson said the boy's parents were trying to get him out while another man called 911.
Isaacson broke the glass door of a coffee shop to get a fire extinguisher to help save the boy.
Isaacson said a trooper later told her she would need to pay to replace the glass door or could face burglary charges.
No charges have been filed yet.