tecnica:motori:obd-ii
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OBD-II On-Board Diagnostics
See Wikipedia On-board_diagnostics.
ECU | Eengine Control Unit: controls a series of actuators on an internal combustion engine to ensure optimal engine performance. |
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DTC | Diagnostic Trouble Code: 4-digits, preceded by a letter: P for engine and transmission (powertrain), B for body, C for chassis, and U for network, |
PID | On-board diagnostics Parameter IDs, codes used to request data from a vehicle. |
Service | OBD-II standard (SAE J1979) defines several services (or modes) used to communicate with the ECU. There is a service to request PIDs data, a service to clear DTC, etc. |
MIL/CEL | Malfunction Indicator Lamp/Check Engine Light, typically has amber color. When the MIL is lit, the engine control unit stores a fault code DTC related to the malfunction. |
Freeze Frame | When the check engine light turn on, the ECU determines the error based on several engine operating conditions and stores it in what’s called a OBDII freeze frame. The data stored in Freeze Frame is usually recorded when a system fails the first time for two consecutive trip faults. Freeze Frame data will only be overwritten by a different fault with a higher priority. |
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tecnica/motori/obd-ii.1533185846.txt.gz · Last modified: 2018/08/02 06:57 by niccolo