Description of On-Board Diagnostics
DESCRIPTIONThe Electronic Control Unit (ECU) contains a built-in self-diagnosis system by which troubles with the engine signal network are detected and a check engine warning light on the instrument panel flashes.
By analyzing various signals the ECU detects system malfunctions which are related to the various operating parameters of the sensors or actuators. The ECU stores the failure code(s) associated with the detected failure until the diagnosis system is cleared by removing the Electronic Fuel Injection (EFI) fuse with the ignition switch "OFF".
The check engine warning light on the instrument panel informs the driver that a malfunction has been detected. The light goes out automatically when the malfunction has been cleared.
CHECK ENGINE WARNING LIGHT CHECK
1. The check engine warning light will come on when the ignition switch is placed at "ON" and the engine is not running.
2. When the engine is started, the check engine warning light should go out. If the light remains on, the diagnosis system has detected a malfunction or abnormality in the system.