1|Page
California Smog Check Inspector Licensing
Exam | Latest Verified Questions and
Detailed Answers
OVERVIEW DESCRIPTION
This Comprehensive set of multiple choice questions is designed for the California
Smog Check Inspector Licensing Exam, a closed-book test administered by the Bureau
of Automotive Repair (BAR). It rigorously evaluates a candidate's understanding of
state emission laws and inspection procedures, covering emissions control systems
and theory, visual and functional inspection protocols, OBD I and OBD II diagnostics,
proper operation of BAR-OIS and legacy BAR-97 emissions inspection equipment,
loaded-mode ASM and Two-Speed Idle tailpipe testing, and California-specific rules
including program area variations, STAR station requirements, tamper detection, and
referee label regulations.
QUESTION 1
During acceleration simulation mode (ASM) 50/15, a vehicle is tested at 50% load. What
vehicle speed is simulated during this test?
A. 15 mph
B. 25 mph
C. 50 mph
D. 15 mph for the first phase, 50 mph for the second
CORRECT ANSWER: A. 15 mph
EXPERT RATIONALE: The ASM 5015 test is performed at a simulated speed of 15 mph
with 50% load; the numbers refer to load percentage and speed in mph.
QUESTION 2
The ASM 2525 test subjects a vehicle to what load and simulated speed?
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A. 25% load at 25 mph
B. 25% load at 50 mph
C. 50% load at 15 mph
D. 50% load at 25 mph
CORRECT ANSWER: A. 25% load at 25 mph
EXPERT RATIONALE: ASM 2525 uses 25% load and a simulated speed of 25 mph,
providing a light-load, higher-speed evaluation.
QUESTION 3
Which BAR-specified inspection system must be used for OBD testing on 2000 and
newer gasoline vehicles in Enhanced areas?
A. BAR-97 EIS
B. BAR-OIS
C. BAR-90
D. BAR-DAD
CORRECT ANSWER: B. BAR-OIS
EXPERT RATIONALE: BAR-OIS (OBD Inspection System) is the current platform for OBD-
only and OBD-plus-loaded-mode testing, replacing BAR-97 for most vehicles.
QUESTION 4
A vehicle fails the ASM 50/15 test with excessive HC and CO but passes NOx. What is
the most likely cause?
A. Lean misfire
B. Rich misfire or incomplete combustion
C. Excessive EGR flow
D. Faulty catalytic converter in reduction stage
CORRECT ANSWER: B. Rich misfire or incomplete combustion
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EXPERT RATIONALE: High HC and CO together indicate a rich condition or misfire, while
NOx remains low because excess fuel cools combustion temperatures.
QUESTION 5
During a Two-Speed Idle (TSI) test, emissions are measured at which two engine
speeds?
A. Idle and 1500 rpm
B. Idle and 2500 rpm
C. 1500 rpm and 2500 rpm
D. 2500 rpm and 4000 rpm
CORRECT ANSWER: B. Idle and 2500 rpm
EXPERT RATIONALE: The TSI test collects samples with the engine at normal idle and at
a steady 2500 rpm, evaluating no-load emissions.
QUESTION 6
What is the primary purpose of the Evaporative Emission Control (EVAP) system?
A. Reduce NOx by recirculating exhaust gas
B. Prevent fuel vapors from escaping into the atmosphere
C. Burn excess fuel during deceleration
D. Inject secondary air into the exhaust
CORRECT ANSWER: B. Prevent fuel vapors from escaping into the atmosphere
EXPERT RATIONALE: The EVAP system captures fuel vapor from the tank and uses a
charcoal canister to store them until they are purged into the intake manifold.
QUESTION 7
A BAR-97 EIS machine will abort the ASM test if the vehicle’s engine RPM deviates from
the target speed by more than:
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A. ±100 RPM
B. ±200 RPM
C. ±300 RPM
D. ±500 RPM
CORRECT ANSWER: C. ±300 RPM
EXPERT RATIONALE: The dynamometer control system requires engine RPM to stay
within ±300 RPM of the target for the test to remain valid; larger deviations cause an
abort.
QUESTION 8
Which of the following is an example of a functional test performed during a Smog
Check inspection?
A. Checking the vehicle's tire pressure
B. Inspecting the gas cap with a pressure/vacuum tester
C. Measuring battery voltage
D. Scanning for transmission codes
CORRECT ANSWER: B. Inspecting the gas cap with a pressure/vacuum tester
EXPERT RATIONALE: Functional testing verifies system operation; the gas cap test
ensures the EVAP system can hold pressure and is a required functional check.
QUESTION 9
A vehicle’s OBD II Data Link Connector (DLC) must be located within how many inches
of the driver’s side steering column centerline?
A. 12 inches
B. 18 inches
C. 24 inches
California Smog Check Inspector Licensing
Exam | Latest Verified Questions and
Detailed Answers
OVERVIEW DESCRIPTION
This Comprehensive set of multiple choice questions is designed for the California
Smog Check Inspector Licensing Exam, a closed-book test administered by the Bureau
of Automotive Repair (BAR). It rigorously evaluates a candidate's understanding of
state emission laws and inspection procedures, covering emissions control systems
and theory, visual and functional inspection protocols, OBD I and OBD II diagnostics,
proper operation of BAR-OIS and legacy BAR-97 emissions inspection equipment,
loaded-mode ASM and Two-Speed Idle tailpipe testing, and California-specific rules
including program area variations, STAR station requirements, tamper detection, and
referee label regulations.
QUESTION 1
During acceleration simulation mode (ASM) 50/15, a vehicle is tested at 50% load. What
vehicle speed is simulated during this test?
A. 15 mph
B. 25 mph
C. 50 mph
D. 15 mph for the first phase, 50 mph for the second
CORRECT ANSWER: A. 15 mph
EXPERT RATIONALE: The ASM 5015 test is performed at a simulated speed of 15 mph
with 50% load; the numbers refer to load percentage and speed in mph.
QUESTION 2
The ASM 2525 test subjects a vehicle to what load and simulated speed?
,2|Page
A. 25% load at 25 mph
B. 25% load at 50 mph
C. 50% load at 15 mph
D. 50% load at 25 mph
CORRECT ANSWER: A. 25% load at 25 mph
EXPERT RATIONALE: ASM 2525 uses 25% load and a simulated speed of 25 mph,
providing a light-load, higher-speed evaluation.
QUESTION 3
Which BAR-specified inspection system must be used for OBD testing on 2000 and
newer gasoline vehicles in Enhanced areas?
A. BAR-97 EIS
B. BAR-OIS
C. BAR-90
D. BAR-DAD
CORRECT ANSWER: B. BAR-OIS
EXPERT RATIONALE: BAR-OIS (OBD Inspection System) is the current platform for OBD-
only and OBD-plus-loaded-mode testing, replacing BAR-97 for most vehicles.
QUESTION 4
A vehicle fails the ASM 50/15 test with excessive HC and CO but passes NOx. What is
the most likely cause?
A. Lean misfire
B. Rich misfire or incomplete combustion
C. Excessive EGR flow
D. Faulty catalytic converter in reduction stage
CORRECT ANSWER: B. Rich misfire or incomplete combustion
,3|Page
EXPERT RATIONALE: High HC and CO together indicate a rich condition or misfire, while
NOx remains low because excess fuel cools combustion temperatures.
QUESTION 5
During a Two-Speed Idle (TSI) test, emissions are measured at which two engine
speeds?
A. Idle and 1500 rpm
B. Idle and 2500 rpm
C. 1500 rpm and 2500 rpm
D. 2500 rpm and 4000 rpm
CORRECT ANSWER: B. Idle and 2500 rpm
EXPERT RATIONALE: The TSI test collects samples with the engine at normal idle and at
a steady 2500 rpm, evaluating no-load emissions.
QUESTION 6
What is the primary purpose of the Evaporative Emission Control (EVAP) system?
A. Reduce NOx by recirculating exhaust gas
B. Prevent fuel vapors from escaping into the atmosphere
C. Burn excess fuel during deceleration
D. Inject secondary air into the exhaust
CORRECT ANSWER: B. Prevent fuel vapors from escaping into the atmosphere
EXPERT RATIONALE: The EVAP system captures fuel vapor from the tank and uses a
charcoal canister to store them until they are purged into the intake manifold.
QUESTION 7
A BAR-97 EIS machine will abort the ASM test if the vehicle’s engine RPM deviates from
the target speed by more than:
, 4|Page
A. ±100 RPM
B. ±200 RPM
C. ±300 RPM
D. ±500 RPM
CORRECT ANSWER: C. ±300 RPM
EXPERT RATIONALE: The dynamometer control system requires engine RPM to stay
within ±300 RPM of the target for the test to remain valid; larger deviations cause an
abort.
QUESTION 8
Which of the following is an example of a functional test performed during a Smog
Check inspection?
A. Checking the vehicle's tire pressure
B. Inspecting the gas cap with a pressure/vacuum tester
C. Measuring battery voltage
D. Scanning for transmission codes
CORRECT ANSWER: B. Inspecting the gas cap with a pressure/vacuum tester
EXPERT RATIONALE: Functional testing verifies system operation; the gas cap test
ensures the EVAP system can hold pressure and is a required functional check.
QUESTION 9
A vehicle’s OBD II Data Link Connector (DLC) must be located within how many inches
of the driver’s side steering column centerline?
A. 12 inches
B. 18 inches
C. 24 inches
