On November 28, 2025, I experienced a vehicle fire in my Mercedes 2020 Sprinter 2500 4WD van. The van engine was on and idling while heating up with the van heater blower on level 6 (out of 7). After about 45 minutes, I saw a haze first and then smelled smoke. Unsure of the source, I turned the vehicle off and exited with my dog. I opened the hood to look for smoke in the engine bay. No smoke under the hood. I contact Mercedes Roadside and open the driver side door where I see flames under the seat. I grabbed the fire extinguisher I installed and put the fire out within 20-25 seconds of seeing it. I believe the root cause of the fire was running the van blower at a high setting for a sustained 45 minutes. My dog and I were inside and definitely in danger. It scares me to think of a scenario where the van was idling with only my dog inside and something like this occurring. The incident is currently under investigation with MB USA and my insurance company, Progressive. No warning signs or dashboard messages. In general, the electrical wiring for my vehicle has been spotty and was completely rewired by the dealer service center in 2021. Currently, there is an issue blacking out the dashboard screen so there is no screen function including gps, entertainment, or vehicle info.