On-Board Diagnostic System Description

On-Board Diagnostic System Description

The P/S control module performs the on-board diagnosis (self-diagnosis) on the system and operates the "EPS" warning light (1) as follows.

- The "EPS" warning light lights when the ignition switch is turned to ON position (but the engine at stop) regardless of the condition of the P/S control system. This is only to check if the "EPS" warning light is operated properly.
- If the areas monitored by the P/S control module is free from any trouble after the engine start (while engine is running), the "EPS" warning light turns OFF.
- When the P/S control module detects a trouble which has occurred in the monitored areas the "EPS" warning light comes ON while the engine is running to warn the driver of such occurrence of the trouble and at the same time it stores the exact trouble area in memory inside of the P/S control module.






Driving Cycle

A "Driving Cycle" consists of engine startup and engine shutoff.

3 Driving Cycles Detection Logic

The malfunction detected in the first and second driving cycle is stored in P/S control module memory (in the form of pending DTC) but the "EPS" warning light does not light at these time. It lights up at the third detection of same malfunction also in the next driving cycle.