OBD-II
The standardized on-board diagnostics system, mandatory on US-market vehicles since 1996, that reports diagnostic trouble codes and live sensor data through a common 16-pin connector.
OBD-II (On-Board Diagnostics, second generation) standardizes how a vehicle's onboard computer reports faults and live data, regardless of make. Any generic scan tool can pull codes through the same 16-pin connector, usually under the dashboard.
See also
- Diagnostic Trouble Code (DTC)A standardized alphanumeric code (e.g. P0299) that a vehicle's computer sets when it detects a fault, pointing a technician toward the affected system and circuit.
- Engine Control Unit (ECU)The onboard computer that manages fuel injection, ignition timing, and dozens of other engine functions using real-time input from the vehicle's sensors.
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