FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Diagnostic Test Mode

DIAGNOSTIC TEST MODE
When an abnormality is detected in one of the sensors or actuators related to emission control, the CHECK ENGINE/MALFUNCTION INDICATOR LAMP illuminates as a warning to the driver.

When an abnormality is detected in one of the sensors or actuators, a diagnostic trouble code corresponding to the abnormality is output.

The RAM data inside the ECM that is related to the sensors and actuators can be read by means of the scan tool. In addition, the actuators can be controlled under certain circumstances.