SMOG CHECK MANUAL - FUNCTIONAL
TESTS QUESTIONS AND ANSWERS
WITH COMPLETE SOLUTIONS 100%
CORRECT RATED A+
MIL Functional Test Procedures
Q: What is the purpose of the MIL functional test? A: To verify that the MIL
bulb is not burned out, taped over, or otherwise tampered with, and that the
engine's Powertrain Control Module (PCM) is capable of commanding the light to
turn on.
Q: What happens during the KOEO (Key On, Engine Off) position? A: When
you turn the ignition to "ON" but do not start the engine, the MIL must illuminate.
This confirms the bulb is functional and the system is in a self-test mode.
Q: What happens during the KOER (Key On, Engine Running) position? A:
Once the engine is started, the MIL should extinguish (turn off). This indicates
that the system has completed its self-check and has not currently detected any
active emission-related faults.
Q: What is the result if the MIL does not illuminate at all during the KOEO
phase? A: The vehicle fails the inspection. A non-illuminated MIL suggests a
potential bulb failure, a wiring issue, or deliberate tampering (such as a blocked
light) intended to hide existing diagnostic trouble codes (DTCs).
Fail -ANSWER ✔✔If the MIL illuminates continuously during the MIL functional
test, what are the results of the test?
Fail -ANSWER ✔✔If the MIL flashes with the engine running during the MIL
functional test, what are the results of the test?
, Using the vehicle manufacturer's procedure to complete the KOEO/KOER
sequences -ANSWER ✔✔For vehicles with keyless ignition systems, how should
the MIL functional test be completed?
No -ANSWER ✔✔Are maintenance reminder lights part of the Smog Check
inspection?
14,000 lbs -ANSWER ✔✔Most vehicles with a GVWR greater than this are not
equipped with an OBD II system.
The OBD II functional test is not performed on these vehicles -ANSWER ✔✔How
should an inspector proceed with the OBD II functional test if a vehicle is not
equipped with an OBD II system?
OBD II functional test -ANSWER ✔✔This test evaluates and reports the status
and/or results of the readiness monitors, system faults, and MIL.
When prompted by the EIS or OIS -ANSWER ✔✔During an OBD II functional
test, when should the inspector connect the DLC to the vehicle?
Refer to the appropriate electronic component location manual or emission control
diagnostic and repair manual -ANSWER ✔✔What should the inspector do if they
are unable to find the DLC?
Problems communicating with the OBD II system -ANSWER ✔✔This condition
may constitute a failure of the OBD II functional test:
TESTS QUESTIONS AND ANSWERS
WITH COMPLETE SOLUTIONS 100%
CORRECT RATED A+
MIL Functional Test Procedures
Q: What is the purpose of the MIL functional test? A: To verify that the MIL
bulb is not burned out, taped over, or otherwise tampered with, and that the
engine's Powertrain Control Module (PCM) is capable of commanding the light to
turn on.
Q: What happens during the KOEO (Key On, Engine Off) position? A: When
you turn the ignition to "ON" but do not start the engine, the MIL must illuminate.
This confirms the bulb is functional and the system is in a self-test mode.
Q: What happens during the KOER (Key On, Engine Running) position? A:
Once the engine is started, the MIL should extinguish (turn off). This indicates
that the system has completed its self-check and has not currently detected any
active emission-related faults.
Q: What is the result if the MIL does not illuminate at all during the KOEO
phase? A: The vehicle fails the inspection. A non-illuminated MIL suggests a
potential bulb failure, a wiring issue, or deliberate tampering (such as a blocked
light) intended to hide existing diagnostic trouble codes (DTCs).
Fail -ANSWER ✔✔If the MIL illuminates continuously during the MIL functional
test, what are the results of the test?
Fail -ANSWER ✔✔If the MIL flashes with the engine running during the MIL
functional test, what are the results of the test?
, Using the vehicle manufacturer's procedure to complete the KOEO/KOER
sequences -ANSWER ✔✔For vehicles with keyless ignition systems, how should
the MIL functional test be completed?
No -ANSWER ✔✔Are maintenance reminder lights part of the Smog Check
inspection?
14,000 lbs -ANSWER ✔✔Most vehicles with a GVWR greater than this are not
equipped with an OBD II system.
The OBD II functional test is not performed on these vehicles -ANSWER ✔✔How
should an inspector proceed with the OBD II functional test if a vehicle is not
equipped with an OBD II system?
OBD II functional test -ANSWER ✔✔This test evaluates and reports the status
and/or results of the readiness monitors, system faults, and MIL.
When prompted by the EIS or OIS -ANSWER ✔✔During an OBD II functional
test, when should the inspector connect the DLC to the vehicle?
Refer to the appropriate electronic component location manual or emission control
diagnostic and repair manual -ANSWER ✔✔What should the inspector do if they
are unable to find the DLC?
Problems communicating with the OBD II system -ANSWER ✔✔This condition
may constitute a failure of the OBD II functional test:
