Use the OBD-II trouble code lookup to find the meaning of any DTC for your car. Enter codes like P0171, C0035 or U0401 and see what they mean in plain language.
You’ll get official SAE definitions plus real-world symptoms, common causes and repair steps for P, B, C and U codes on all OBD-II compliant vehicles.
AutoDTCs.com is a complete OBD-II trouble code lookup for all vehicles. We cover every generic P-, B-, C- and U-code defined in the official SAE J2012-DA standard, including powertrain, chassis, body, network and hybrid/EV systems. Each page is written by professional automotive technicians.
Whether your scan tool shows a check engine light, ABS or ESP warning, airbag fault, hybrid battery issue or CAN communication problem, you’ll find clear, step-by-step diagnostic guidance and repair information here.
Powertrain (P-Codes) are diagnostic trouble codes related to the engine, transmission, fuel/air delivery, emissions, and hybrid or EV propulsion systems. These faults often affect drivability, performance, fuel economy, or emissions compliance.Browse powertrain subsystems: Engine & Powertrain · Fuel & Air Metering · Ignition & Misfire · Emission System · Cooling Systems · Transmission · Hybrid / EV Propulsion
Body (B-Codes) are diagnostic trouble codes associated with body and comfort systems including interior electronics, lighting, power accessories, SRS safety systems, and HVAC controls. These faults can affect usability, safety, or passenger comfort.Browse body subsystems: Body / Comfort & Interior · Climate Control / HVAC · Airbag / SRS
Chassis (C-Codes) are diagnostic trouble codes associated with vehicle dynamics systems such as ABS, traction and stability control, steering, suspension, and driveline components. These faults can affect handling, braking, and overall vehicle safety.Browse chassis subsystems: ABS / Traction / Stability · Steering Systems · Suspension Systems · Wheels / Driveline
Network (U-Codes) are diagnostic trouble codes related to communication between control modules over vehicle networks such as CAN bus. These faults may cause warning lights, intermittent issues, feature failures, or loss of communication between systems.Browse network subsystems: CAN Bus / Network Communication · Control Module Communication · Vehicle Integration Systems
Type the code from your scan tool (for example P0171, C0035 or U0401) into the search box at the top of this page. Each result shows the official SAE definition, common causes, symptoms and repair steps.
Yes. Generic P0xxx codes follow the OBD-II standard and have the same meaning for every make and model. Manufacturer-specific codes usually use P1xxx ranges or brand-specific B, C or U codes.
P-codes relate to the powertrain and emissions, B-codes to body and airbag systems, C-codes to chassis and ABS, and U-codes to module communication and CAN network faults.
Yes. AutoDTCs.com includes hybrid and EV trouble codes for high-voltage batteries, isolation faults, inverters, onboard chargers and other electric drive components.
The information applies to all OBD-II compliant vehicles, including Audi, BMW, Mercedes-Benz, Toyota, Honda, Ford, GM, Volkswagen and many more brands.