A car problem is inconvenient anywhere, but a breakdown on a high-speed highway can become a safety emergency within seconds. Passing vehicles may be traveling at freeway speeds, shoulders may be narrow, and other drivers may not immediately recognize that your vehicle is disabled.
Your first objective is not diagnosing the mechanical problem. It is getting yourself, your passengers, and the vehicle into the safest situation reasonably available.
Stay in Control and Move Away From Traffic If Possible
If you notice a warning light, loss of power, unusual vibration, tire problem, overheating, or another serious issue, avoid abrupt movements. Signal your intentions, reduce speed smoothly, and look for a safer place to stop.
If the vehicle can still move safely, an exit, rest area, parking lot, or location completely separated from highway traffic is generally preferable to stopping on a narrow shoulder.
If you cannot reach an exit, move as far away from the travel lane as safely possible while remaining on stable ground.
Turn On Your Hazard Lights
Activate your emergency flashers as soon as you realize the vehicle is becoming disabled. Visibility is particularly important at night, during rain, fog, or other low-visibility conditions.
If your vehicle stops in an active traffic lane and cannot move, call 911 or the appropriate emergency service promptly. Tell the dispatcher that the vehicle is blocking traffic and follow the instructions you receive.
Decide Whether Remaining in the Vehicle Is Safer
There is no single answer for every roadside emergency. Your safest action depends on where the vehicle stops, surrounding traffic, barriers, weather, visibility, fire risk, and other conditions.
If the vehicle is well off the road in a reasonably protected location, remaining inside with your seat belt fastened may reduce your exposure to passing traffic.
If the vehicle is in an active lane, is at immediate risk of being struck, is smoking or burning, or presents another serious hazard, you may need to move to a safer location. Exit only when you can do so without stepping into traffic, and move away from the roadway where practical.
Emergency dispatchers, police, fire personnel, and roadside professionals may give instructions based on the specific scene. Follow their directions.
Call for Help and Give an Accurate Location
Once you are in the safest position available, contact roadside assistance, law enforcement, emergency services, or another appropriate provider.
Your location information can make a major difference in response time. Look for interstate numbers, direction of travel, exit numbers, mile markers, cross streets, bridges, businesses, or recognizable landmarks.
Use Your Phone’s Location Tools
Navigation apps can help identify your approximate position, but do not assume a roadside provider automatically knows where you are. Confirm the location verbally or through the provider’s app when possible.
Tell the Dispatcher About Special Hazards
Mention if the vehicle is partly in a travel lane, stopped on a bridge, near a blind curve, carrying vulnerable passengers, leaking fluid, smoking, or experiencing another unusual problem. This helps responders understand the situation before arriving.
Avoid Risky Roadside Repairs
A highway shoulder is not the same as a driveway or repair shop. Even a task that normally takes only a few minutes can expose you to high-speed traffic.
Do not stand directly in front of or behind your vehicle where approaching motorists may have difficulty seeing you. Avoid working on the traffic-facing side of a vehicle when passing cars are nearby.
Changing a tire, inspecting an engine, or placing warning devices may not be safe on a narrow or busy shoulder. When in doubt, call for professional assistance instead of attempting a repair beside moving traffic.
AAA’s roadside breakdown guidance similarly emphasizes visibility, moving away from traffic where possible, and calling for assistance.
Keep an Emergency Roadside Kit in Your Vehicle
Preparation can make a breakdown less difficult. The National Highway Traffic Safety Administration recommends carrying an emergency roadside kit even in a well-maintained vehicle.
Useful supplies can include a charged phone and charger, flashlight, first aid kit, jumper cables, tire pressure gauge, work gloves, drinking water, nonperishable food, emergency blankets, basic tools, and other supplies appropriate for your climate and trip.
Think About Your Passengers
Children, older adults, people with mobility limitations, and pets can make a roadside emergency more complicated. Before deciding to move everyone out of the vehicle, consider whether doing so would expose them to traffic.
Keep passengers calm and explain what is happening. If remaining inside the vehicle is the safest option, everyone should generally stay buckled rather than moving around unnecessarily.
If you must evacuate because of fire or another immediate danger, move everyone to a location well away from traffic as quickly and safely as conditions allow.
What Other Drivers Should Do Around a Breakdown
Disabled vehicles create risks not only for occupants but also for tow operators, emergency responders, highway workers, and passing motorists.
NHTSA explains that all states have Move Over laws covering emergency vehicles with flashing lights, although the exact scope of these laws varies. When approaching roadside flashing lights, drivers should follow applicable state requirements, move to a non-adjacent lane when safely possible, or slow appropriately when a safe lane change cannot be made.
You can review NHTSA’s Move Over guidance before your next trip.
Reduce the Chance of a Breakdown Before a Road Trip
No maintenance routine can guarantee that a vehicle will never fail, but checking basic systems before a long journey can reduce avoidable problems.
Inspect tire condition and pressure, fluid levels, lights, windshield wipers, battery condition, and any warning indicators. Address unusual noises or dashboard warnings before beginning a long highway trip.
If you are planning a remote scenic drive, review our guide to scenic highways worth adding to your road-trip list and research services available along the route.
Electric Vehicles Need Emergency Planning Too
An EV does not eliminate the possibility of roadside trouble. Tire damage, 12-volt battery problems, collisions, component failures, or unexpectedly low charge can still leave a vehicle disabled.
EV travelers should identify charging options and roadside assistance before leaving. Our 2026 EV road-trip planning guide explains how to build backup charging options into a long-distance route.
Safety Comes Before the Vehicle
When a car breaks down on the highway, it is natural to focus immediately on what failed. On a busy roadway, however, the more important question is whether you and your passengers are protected from traffic.
Move away from moving lanes when the vehicle can do so safely, make yourself visible, contact appropriate help, and avoid unnecessary exposure on the shoulder. Mechanical repairs can wait until the immediate roadside risk is under control.