Which scenario allows a vehicle to pass a smog check despite having the MIL on?

In the context of a smog check, the Malfunction Indicator Lamp (MIL) plays a crucial role in assessing the vehicle's emissions system. When the MIL is illuminated, it typically indicates that the vehicle's onboard diagnostic system has detected a problem that could affect emission levels. However, if the functional test of the MIL is completed successfully, it signifies that the light is working properly and that the system can monitor for faults effectively.

Passing the MIL functional test implies that the vehicle's onboard diagnostics are operational. In this case, even if the MIL is on, it can be allowed to pass if the issues it indicates do not directly pertain to the vehicle's emissions compliance status at the time of testing. This means that while there may be a fault indicated by the MIL, it could be for a non-emission-related issue, allowing the vehicle to meet the necessary requirements for passing the smog check.

By contrast, if the MIL remains on during the test without being verified as operational or if there are diagnostic trouble codes (DTCs) present, the vehicle would typically fail the inspection, as these factors indicate potential emission control system issues. Clearing DTCs after the test does not enable a vehicle to pass, as that would undermine the integrity