Why Parked Cars Catch Fire: Causes, Risks, and How to Prevent Them

Cars can catch fire while parked primarily due to electrical faults that remain energized even when the ignition is off, battery failures (12-volt or high-voltage in hybrids/EVs), lingering heat igniting combustibles, and, less commonly, fuel leaks, aftermarket wiring, charging equipment issues, or arson. This article explains how such fires start, what warning signs to watch for, recent recall examples, and practical steps to reduce risk.

How a Parked Vehicle Can Ignite

Even when a car is off, multiple systems stay powered or wake periodically—security modules, telematics, keyless entry receivers, battery management, and, for EVs, high-voltage components during charging or thermal management. These pathways, combined with heat, fuel, and oxygen, can create ignition sources in a stationary vehicle.

• Always-live 12-volt circuits: Short circuits in fuse boxes, harnesses, relays, or add-on devices (alarms, dashcams, trackers) can overheat wiring and ignite insulation or nearby plastics.
• Battery failures: Internal shorting in a 12V lead-acid battery or poor/loose terminals can spark and overheat; lithium-ion cells in hybrids/EVs can enter thermal runaway if damaged or defective.
• Charging and external power: Faulty EV chargers/cords, household outlets, block heaters, battery tenders, or improperly fused aftermarket power feeds can overheat or arc.
• Moisture intrusion: Water in control modules (e.g., ABS pump/controller, tow-hitch modules) can cause corrosion, bridging, and delayed electrical shorts hours or days after exposure.
• Residual heat: Recently driven catalytic converters and exhaust parts can ignite dry vegetation or debris if the vehicle is parked over grass, leaves, or paper.
• Fuel and vapor leaks: A gasoline or diesel leak may be ignited by an electrical spark, static discharge, or a hot surface, even with the engine off.
• Devices and contents: Charging power banks, e-bikes/scooters, or lithium batteries left in the cabin/trunk can fail; aerosol cans can burst if heated by sun or residual engine heat.
• Arson and external sources: Intentional ignition, nearby structure fires, wildfires, or lightning can set a parked vehicle ablaze.

These scenarios are uncommon on any given day, but they explain why parked-vehicle fires do occur and why they often trace back to energized circuits, heat, or vulnerable components.

Why Fires Can Start Hours After You Park

“Delayed ignition” is common. Modules may wake on timers, respond to key fobs or connectivity pings, or balance batteries. Moisture-driven corrosion can turn into a short only after it bridges conductors. Thermal soak raises component temperatures for an hour or more post-drive. In EVs and hybrids, cooling pumps, contactors, onboard chargers, and DC/DC converters may cycle at rest, providing both power and heat pathways.

Recent Recall Examples Involving Parked-Vehicle Fire Risk

Several high-profile recalls in recent years specifically warned owners to park outside and away from structures because fires could occur while parked and off. This underscores that energized components and moisture intrusion can pose risks even when vehicles are stationary.

• Hyundai and Kia ABS/HECU modules: Multiple recalls (various models/years through 2023) for moisture intrusion causing internal shorts that could lead to under-hood fires while parked; owners were advised to park outside until repairs.
• Hyundai Palisade and Kia Telluride tow-hitch harness modules (2022–2023): Water ingress could cause a short and fire risk with the vehicle off; dealers added fusing and replaced harnesses as needed.
• Chevrolet Bolt EV (2017–2022): Battery defects could cause thermal runaway during charging or at rest; GM advised parking outside, limiting charge levels, and later replaced battery modules and updated software.
• Ford Expedition/Navigator (2021–2022): Under-hood fire risk tied to electrical components; Ford urged owners to park outside until remedies were completed.
• GM truck/SUV engine block heater cord recalls (various late-2010s models): Damaged cords and connections could overheat and ignite while the vehicle was parked and plugged in.

Owners can check for open recalls anytime using their VIN at official portals (e.g., NHTSA in the U.S.), and should follow interim parking guidance if advised.

Warning Signs to Watch For

Subtle clues often precede an ignition event. Paying attention to smells, sounds, and small electrical anomalies can help you act before a fire starts.

• Electrical smell (hot plastic/insulation) after parking or when the car is locked.
• Frequent clicking from relays or modules with the key off; fans or pumps cycling unexpectedly.
• Warm hood or grille area long after a short drive; wisps of smoke or vapor under the hood.
• Rapid 12V battery drain, repeated dead battery, or fuses that blow repeatedly.
• Moisture in the cabin/engine bay, water leaks near fuse boxes or control modules.
• Warning lights, charging faults, or “service electrical system” messages.
• Unusual odors while an EV is charging; charge equipment that runs hot or trips breakers.

If you notice one or more of these signs, disconnect external power if safe, park the vehicle outside and away from structures, and have it inspected promptly.

How to Lower the Risk

Most preventative actions are simple and inexpensive. They focus on keeping energized circuits safe, reducing heat exposure, and removing combustible materials from potential ignition sources.

• Park smart: Avoid dry grass or leaf piles after driving; clear debris from the engine bay and cowl drains.
• Mind electricity: Use quality, fused wiring for any aftermarket device; avoid piggybacking circuits; don’t run chargers on damaged cords or non-GFCI outlets.
• Use proper EV charging: Plug directly into a dedicated, properly rated circuit; avoid extension cords; follow manufacturer charge limits and software updates; don’t charge a damaged vehicle or battery.
• Check for recalls: Run your VIN on your national safety website; schedule remedy work promptly, and follow any “park outside” guidance until fixed.
• Battery care: Keep 12V terminals clean and tight; replace swollen, leaking, or weak batteries; in EVs/hybrids, get high-voltage systems inspected after any impact or flood exposure.
• Fix leaks and smells: Address fuel, oil, or coolant leaks quickly; investigate burning smells or repeated fuse failures.
• Be cautious with devices: Don’t leave e-bike/scooter batteries or cheap power banks charging in the car; avoid aerosol cans in hot interiors.

These steps don’t eliminate risk entirely, but they substantially reduce the most common ignition pathways in parked vehicles.

What To Do If You Suspect a Fire While Parked

Fast, safe action can prevent escalation and protect people and property. Treat smoke or strong burning smells seriously, especially in enclosed garages.

• Do not open the hood—introducing air can intensify a fire.
• Call emergency services immediately; give your exact location and mention if the vehicle is electric or hybrid.
• If connected to power, shut off charging at the breaker or EVSE stop button if it’s safe and you are trained to do so.
• Use a fire extinguisher only for very small, accessible fires and only if you have a clear escape route.
• Move nearby vehicles and people away; EV battery fires can reignite and release toxic smoke.
• Notify your insurer and do not re-energize or attempt to restart the vehicle.

Prioritizing personal safety and calling professionals early is crucial; vehicle fires can escalate quickly and produce hazardous fumes.

Insurance, Liability, and Documentation

Comprehensive auto insurance typically covers fire damage to your vehicle; homeowners or building policies may address related structure damage. If a defect or recalled component is involved, your insurer may pursue subrogation from a manufacturer or supplier. Keep maintenance records, recall notices, charger receipts, and any diagnostic reports; they can be important in claims or investigations.

How Investigators Pinpoint the Cause

Post-fire analysis blends physical evidence with electronic data. While not every cause can be confirmed, established methods help isolate the origin.

• Burn patterns and point of origin to see whether the fire started under the hood, in-cabin, trunk, or externally.
• Evidence of electrical arcing, melted copper, or beading on conductors indicating energized faults.
• Module scans and event data (where available) for error codes, wake/sleep cycles, or charging logs.
• Inspection of batteries and chargers for cell venting, thermal runaway markers, or connector damage.
• Interviews, weather, and surveillance to rule out arson or external ignition sources.

Findings often fall into mechanical/electrical failure, charging-related issues, or external causes—guiding recalls, repairs, or legal outcomes.

Summary

Parked cars can catch fire when energized electrical circuits short, batteries fail, heat ignites nearby combustibles, or external power and devices malfunction; moisture intrusion and recent driving heat often play a role. Stay ahead of risk by heeding warning signs, keeping up with recalls, charging correctly, maintaining batteries and wiring, and parking thoughtfully. If trouble arises, act quickly, prioritize safety, and seek professional help.

What would cause a parked car to catch fire?

Common Causes of Car Fires
The primary origin of vehicle fires is fuel system leaks. Whether gasoline or diesel, a small leak can become a significant hazard if it contacts hot engine parts, potentially igniting when temperatures exceed 45 degrees Fahrenheit.

Is it rare for a car to catch on fire?

No, car fires are not considered rare; the National Fire Protection Association (NFPA) estimates nearly 300,000 vehicle fires occur each year in the U.S., though the overall risk is low compared to the total number of vehicles on the road. While the number of incidents is down from peak years, there has been a recent uptick in both incidents and associated fatalities. 
Statistics on Vehicle Fires

• Frequency: Roughly 300,000 vehicle fires are estimated to happen each year in the U.S. 
• Risk: Despite the number, the risk per vehicle is low, with approximately 0.04% of registered vehicles catching fire annually. 
• Recent Trends: While the overall number of vehicle fires has decreased since 2005, there has been an increase in incidents and civilian deaths in recent years. 

Common Causes

• Mechanical Failure: A significant cause, often related to engine oil leaks or worn-out components. 
• Electrical Failure: Issues with a vehicle’s wiring or electrical systems can lead to fires. 
• Accidents: Crashes can rupture fuel lines or tanks, leading to fires. 
• Lack of Maintenance: Neglecting maintenance can cause rubber hoses and seals to fail, leading to fluid leaks and potential fires. 
• Flammable Materials: Improper storage of flammable materials, like rags or paper towels, under the hood can ignite. 

Key Takeaways

• Significant Risk: Although not common for a single driver, car fires are a significant risk, contributing to deaths and injuries each year. 
• Prevention: Proper maintenance, addressing recalls, and avoiding the buildup of flammable materials are key ways to prevent fires. 
• Increased Danger: Car fires can escalate rapidly, posing a severe threat to occupants and those nearby. 

What part of a car is most likely to catch fire?

1: Fuel System Leaks. Leaks in the fuel system are the most common cause of vehicle fires, so that’s why they take the top spot on our list. A fuel system leak is really dangerous.

Where do most vehicle fires start?

Most vehicle fires start in the engine compartment, running gear, or wheel area due to mechanical issues like fuel system leaks, electrical system failures, or overheating components. A fuel system leak is particularly dangerous as it introduces highly flammable gasoline into an area with potential ignition sources, like a spark or hot engine part.
 
Common starting points for vehicle fires:

• Engine Compartment: This is the most common area for a fire to begin, often caused by: 
  • Fuel Leaks: Leaks in fuel lines, hoses, or connections can release flammable gasoline that can easily ignite from a spark or heat source. 
  • Electrical Failures: Faulty wiring, short circuits, or other electrical system malfunctions can generate sparks, igniting nearby flammable materials or fluids. 
  • Overheating Components: Parts like the catalytic converter can get extremely hot and ignite road debris or other combustible materials that accumulate around them. 
• Running Gear and Wheel Area: Fires can also start in these areas due to:
  • Mechanical Failures: Problems with the drivetrain, bearings, or other moving parts can create excessive heat. 
  • Road Debris: Debris can get caught on the undercarriage and ignite from heat or friction. 
  • Electrical Issues: Wiring in the wheel wells or near the axles can also fail and spark. 

Why these areas are so prone to fires:

• Proximity to Ignition Sources: The engine compartment is a complex area with many hot components (engine, exhaust) and electrical systems, creating numerous potential ignition points. 
• Presence of Flammable Materials: Cars contain highly flammable liquids like gasoline, oil, and coolant, which can easily ignite if leaked and exposed to heat or sparks. 
• Concentration of Components: The dense arrangement of parts in the engine and running gear makes fire spread rapidly.