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Readiness Indicator

The readiness indicator identifies whether or not all of the monitors have been run. This indicator is used when an emission Inspection Maintenance (IM) test is performed. EPA regulates that certain cities perform an IM test before license plates can be issued. One of the regulations that EPA uses on OBDII equipped vehicles is that, in order to pass the IM test, the vehicle must have had all of the monitors run at least once, and passed. If any monitor fails, the Malfunction Indicator Lamp (MIL) is illuminated, and the vehicle must be serviced before license plates can be issued.

NOTE: If battery voltage is lost to the PCM, the readiness indicator is reset. If the readiness indicator is reset, all of the monitors must be run before the vehicle can pass an IM test.