Where are the sensors on a car?
Sensors are spread across a modern vehicle—from the engine bay to the tires and around the body—supporting everything from engine management to safety and driver assistance.
In this explainer, we map where these sensors live, what they monitor, and how their data helps keep a car running smoothly and safely. We'll group sensors into four broad domains: engine and powertrain, chassis and safety systems, exterior and interior comfort, and advanced driver-assistance systems (ADAS) and external sensing.
Engine and powertrain sensors
These sensors monitor the heart of the vehicle and are concentrated in the engine compartment, feeding the engine control unit with data on timing, fuel, temperatures, and pressures.
- Crankshaft position sensor
- Camshaft position sensor
- Mass air flow (MAF) sensor or equivalent (airflow measurement)
- Manifold absolute pressure (MAP) sensor
- Intake air temperature (IAT) sensor
- Engine coolant temperature sensor
- Oxygen sensors (pre-cat and post-cat)
- Throttle position sensor (TPS)
- Fuel pressure sensor
- Fuel level sensor
- Oil pressure sensor
- Oil temperature sensor
- Knock sensor
- Cam timing/variable valve timing sensors (often housed with cam sensor or as a separate sensor)
In engine bay, these sensors continuously report vital data to the powertrain control module, tuning ignition, fuel delivery, boost, and cooling to optimize performance and emissions.
Chassis, safety, and monitoring sensors
Sensors under and around the car track motion, stability, and occupant safety. They help control braking, traction, and airbag deployment.
- Wheel speed sensors (ABS/ESC)
- Steering angle sensor
- Yaw rate sensor
- Suspension ride height sensors (active suspension systems)
- Tire pressure monitoring system (TPMS) sensors in each tire
- Airbag/occupant crash sensors
- Brake fluid level sensor (in some systems)
These sensors give the vehicle situational awareness, enabling ABS, stability control, TPMS alerts, adaptive suspensions, and appropriate airbag deployment in a crash.
Exterior and interior climate and comfort sensors
Interior and exterior sensors manage climate controls, visibility, and occupant comfort. They are spread across the cabin and the body surface.
- Outside air temperature sensor
- Cabin temperature sensor
- Cabin humidity sensor
- Rain/light sensors (for wipers and automatic headlights)
- Ambient light sensor
- Occupant detection sensor / weight sensor in seats
These sensors optimize heating, ventilation, air conditioning, and comfort features, while also supporting safety systems that respond to occupancy and weather conditions.
ADAS sensors and external sensing systems
Advanced driver-assistance systems rely on external sensing to monitor the road and surrounding traffic. This category includes cameras, radar, lidar, and ultrasonics.
- Forward-facing camera (for lane keeping, traffic sign recognition, and automatic emergency braking)
- Radar sensors (short-, medium-, and long-range) around the front and sometimes rear of the vehicle
- Ultrasonic sensors around bumpers (parking aids, blind-spot monitoring)
- Surround-view cameras or a 360-degree camera system
- LiDAR sensor (present on select models with high-end ADAS or autonomous capabilities)
These external sensors enable features such as adaptive cruise control, lane-centering, automatic emergency braking, blind-spot detection, and assistive parking. The exact mix and placement vary by model and generation.
Summary
In a modern car, sensors are distributed across four broad areas—engine and powertrain, chassis and safety, exterior and interior comfort, and ADAS/external sensing. Each plays a specific role, from monitoring ignition timing and fuel to tracking wheel speed, monitoring tires, sensing weather and occupancy, and feeding data to cameras and radar systems for advanced driver assistance. The number and arrangement of sensors differ by make, model, and year, but the underlying pattern is consistent: sensors are embedded throughout to create a connected, responsive vehicle.
