MIL and on Board Diagnostic System Function

Malfunction Indicator Lamp (MIL)
1. The malfunction indicator lamp will light up when the ignition switch is turned ON without the engine running. This is for checking the blown lamp.
- If the malfunction indicator lamp does not light up, see the WARNING LAMPS AND CHIME.
2. When the engine is started, the malfunction indicator lamp should go off.
If the lamp remains on, the on board diagnostic system has detected an engine system malfunction.




ON BOARD DIAGNOSTIC SYSTEM FUNCTION
The on board diagnostic system has the following four functions.
1. BULB CHECK : This function checks the bulb for damage (blown, open circuit, etc.) of the malfunction indicator lamp.
2. MALFUNCTION WARNING : This is a usual driving condition. When a malfunction is detected twice (2 trip detection logic), the malfunction indicator lamp will light up to inform the driver that a malfunction has been detected.
Only the following malfunctions will light up or blink the MIL even in the
1st trip.
- "Misfire (possible three way catalyst damage)"
- "Three way catalyst function
- "Closed loop control"
3. SELF-DIAGNOSTIC RESULTS : By using this function, the diagnostic trouble codes can be read.
4. FRONT HEATED OXYGEN SENSOR MONITOR : In this mode, the fuel mixture condition (lean or rich) monitored by front heated oxygen sensor can be read.
How to switch the diagnostic test (function) modes and details of the above functions are described later.