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Description of On-Board Diagnostics

SYSTEM OPERATION

A dash mounting warning lamp lights in event of PGM-FI system malfunction. When warning lamp illuminates, trouble codes are read from an LED display on the ECU. Dash warning lamp and LED display operate whenever ignition is turned "ON" and trouble code(s) are stored in ECU memory.

When ignition is switched "OFF," ECU memory for dash warning lamp is erased. The lamp will not light again (except for about 2 seconds as a lamp check when ignition is first turned "ON") unless the same or another problem is detected. However, memory for LED display will remain until deleted by technician.