Description of On-Board Diagnostics

The 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 as shown in the diagnostic code charts, the ECU detects system malfunctions which are related to the various operating parameter sensors or to the actuator. The ECU stores the failure code associated with the detected failure until the diagnostic system is cleared by removing the EFI fuse with ignition switch off.





The "CHECK ENGINE" warning light on the instrument panel alerts the driver that a malfunction has been detected. The light goes out automatically when the malfunction has been corrected.





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 in or abnormality in the system.