Description of On-Board Diagnostics

Fig. 18 Overhead Chassis View:

The self-diagnosis system monitors the signals of various components in order to sense and indicate when a malfunction has occurred. Two indicators are used to detect and pinpoint a specific problem in the system. The ECS warning lamp, located on the instrument panel, illuminates when a problem is sensed. In addition, a light emitting diode (LED) in the control unit flashes a trouble code to indicate a specific component or circuit malfunction. The control unit is located under the dash.



The self-diagnosis system operates in two modes; a U-check mode and a D-check mode. In the U-check mode, those components necessary for proper starting and drive operation are monitored. A malfunction detected while operating in the U-check mode will cause the ECS warning light to illuminate, indicating the need for further diagnosis.