If the MIL light comes on during the Tailpipe Emissions portion of the inspection, what should the technician do?

• A. Enter 'Fail' during the MIL Functional Test.
• B. Clear the MIL and continue testing.
• C. Ignore MIL and proceed.
• D. Note advisory and continue.

Answer: (A)

A lit Malfunction Indicator Lamp during the tailpipe emissions test means there is an emissions-related fault that must be recorded and handled before the vehicle can be considered for a passing result. In this situation you should enter “Fail” in the MIL Functional Test. This documents the fault correctly and prevents a false pass while the check engine light is on. Clearing the light or ignoring it would mask a real problem and misrepresent the vehicle’s emissions status, which isn’t allowed. After repairs are made, the MIL should be cleared and the vehicle retested to ensure it meets standards.