Michigan Secretary Of State
2026/2027/2028 Testing Cycle
100 Questions & Answers | Verified Rationales
Guaranteed Pass | Graded A+
,SECTION 1: COMPUTER CONTROL & SENSOR BASICS (24 Questions)
Q1: A vehicle has a P0101 code set. Technician A says this indicates a mass airflow sensor
performance problem. Technician B says this indicates a manifold absolute pressure sensor
problem. Who is correct?
A. Technician A only
B. Technician B only
C. Both Technician A and Technician B
D. Neither Technician A nor Technician B
Answer: A
Rationale: P0101 is defined as "Mass Air Flow Circuit Range/Performance." The code
specifically relates to the MAF sensor and its circuit, not the MAP sensor.
Q2: The powertrain control module (PCM) is monitoring the oxygen sensor during closed loop
operation. The O2 sensor voltage is fluctuating between 0.1 and 0.9 volts at a rate of 1 to 5 times
per second. What does this indicate?
A. The O2 sensor is functioning correctly
B. The O2 sensor is stuck lean
C. The O2 sensor is contaminated
D. The O2 sensor heater circuit is faulty
Answer: A
Rationale: A properly functioning oxygen sensor should rapidly fluctuate between 0.1 and 0.9
volts in closed loop. This rapid switching indicates the sensor is accurately reporting rich/lean
conditions to the PCM.
Q3: Technician A says the PCM uses the engine coolant temperature (ECT) sensor to determine
fuel enrichment during cold start. Technician B says the PCM uses the intake air temperature
(IAT) sensor to determine fuel enrichment during cold start. Who is correct?
A. Technician A only
B. Technician B only
C. Both Technician A and Technician B
D. Neither Technician A nor Technician B
Answer: C
,Rationale: Both sensors provide critical input during cold start. The ECT tells the PCM the
engine is cold and needs enrichment, while the IAT helps the PCM calculate air density for
proper fuel delivery.
Q4: A vehicle has a P0340 code set. What does this code indicate?
A. Camshaft position sensor circuit malfunction
B. Crankshaft position sensor circuit malfunction
C. Mass airflow sensor circuit malfunction
D. Throttle position sensor circuit malfunction
Answer: A
Rationale: P0340 is the diagnostic trouble code for "Camshaft Position Sensor 'A' Circuit." This
code is set when the PCM detects an intermittent or lost signal from the camshaft position sensor.
Q5: A technician is testing a manifold absolute pressure (MAP) sensor. The sensor signal voltage
should:
A. Be high (approximately 4.5V) at idle and low (approximately 0.5V) at wide open throttle
B. Be low (approximately 0.5V) at idle and high (approximately 4.5V) at wide open throttle
C. Remain constant at all throttle positions
D. Fluctuate rapidly at all times
Answer: B
Rationale: At idle, manifold vacuum is high, so MAP sensor voltage is low (approximately 0.5–
1.5V). At wide open throttle, vacuum drops and pressure increases, so voltage rises
(approximately 4.5V).
Q6: Technician A says the PCM enters closed loop operation when the oxygen sensor reaches
operating temperature. Technician B says the PCM enters closed loop operation when the engine
coolant reaches a predetermined temperature. Who is correct?
A. Technician A only
B. Technician B only
C. Both Technician A and Technician B
D. Neither Technician A nor Technician B
Answer: C
, Rationale: The PCM enters closed loop when both conditions are met: the O2 sensor must reach
operating temperature (typically 600°F) and the engine coolant must reach a minimum
temperature (typically 140–160°F).
Q7: A vehicle has a P0120 code set. What does this code indicate?
A. Throttle position sensor circuit malfunction
B. Engine coolant temperature sensor circuit malfunction
C. Intake air temperature sensor circuit malfunction
D. Oxygen sensor circuit malfunction
Answer: A
Rationale: P0120 is defined as "Throttle/Pedal Position Sensor/Switch 'A' Circuit." This code is
set when the PCM detects an out-of-range signal from the throttle position sensor.
Q8: A technician is checking a throttle position sensor with a scan tool. The TPS voltage reading
jumps erratically when the throttle is slowly opened. What does this indicate?
A. The TPS is functioning correctly
B. The TPS has a dead spot or erratic signal
C. The PCM is faulty
D. The throttle cable is binding
Answer: B
Rationale: An erratic or jumpy TPS signal indicates a worn resistive element or dirty contacts
inside the sensor. The TPS should be replaced.
Q9: Technician A says the PCM uses the vehicle speed sensor (VSS) to control transmission shift
points. Technician B says the PCM uses the VSS for cruise control operation. Who is correct?
A. Technician A only
B. Technician B only
C. Both Technician A and Technician B
D. Neither Technician A nor Technician B
Answer: C
Rationale: The VSS provides vehicle speed data to the PCM, which uses it for multiple functions
including transmission shift scheduling, cruise control, speedometer operation, and torque
converter clutch engagement.
2026/2027/2028 Testing Cycle
100 Questions & Answers | Verified Rationales
Guaranteed Pass | Graded A+
,SECTION 1: COMPUTER CONTROL & SENSOR BASICS (24 Questions)
Q1: A vehicle has a P0101 code set. Technician A says this indicates a mass airflow sensor
performance problem. Technician B says this indicates a manifold absolute pressure sensor
problem. Who is correct?
A. Technician A only
B. Technician B only
C. Both Technician A and Technician B
D. Neither Technician A nor Technician B
Answer: A
Rationale: P0101 is defined as "Mass Air Flow Circuit Range/Performance." The code
specifically relates to the MAF sensor and its circuit, not the MAP sensor.
Q2: The powertrain control module (PCM) is monitoring the oxygen sensor during closed loop
operation. The O2 sensor voltage is fluctuating between 0.1 and 0.9 volts at a rate of 1 to 5 times
per second. What does this indicate?
A. The O2 sensor is functioning correctly
B. The O2 sensor is stuck lean
C. The O2 sensor is contaminated
D. The O2 sensor heater circuit is faulty
Answer: A
Rationale: A properly functioning oxygen sensor should rapidly fluctuate between 0.1 and 0.9
volts in closed loop. This rapid switching indicates the sensor is accurately reporting rich/lean
conditions to the PCM.
Q3: Technician A says the PCM uses the engine coolant temperature (ECT) sensor to determine
fuel enrichment during cold start. Technician B says the PCM uses the intake air temperature
(IAT) sensor to determine fuel enrichment during cold start. Who is correct?
A. Technician A only
B. Technician B only
C. Both Technician A and Technician B
D. Neither Technician A nor Technician B
Answer: C
,Rationale: Both sensors provide critical input during cold start. The ECT tells the PCM the
engine is cold and needs enrichment, while the IAT helps the PCM calculate air density for
proper fuel delivery.
Q4: A vehicle has a P0340 code set. What does this code indicate?
A. Camshaft position sensor circuit malfunction
B. Crankshaft position sensor circuit malfunction
C. Mass airflow sensor circuit malfunction
D. Throttle position sensor circuit malfunction
Answer: A
Rationale: P0340 is the diagnostic trouble code for "Camshaft Position Sensor 'A' Circuit." This
code is set when the PCM detects an intermittent or lost signal from the camshaft position sensor.
Q5: A technician is testing a manifold absolute pressure (MAP) sensor. The sensor signal voltage
should:
A. Be high (approximately 4.5V) at idle and low (approximately 0.5V) at wide open throttle
B. Be low (approximately 0.5V) at idle and high (approximately 4.5V) at wide open throttle
C. Remain constant at all throttle positions
D. Fluctuate rapidly at all times
Answer: B
Rationale: At idle, manifold vacuum is high, so MAP sensor voltage is low (approximately 0.5–
1.5V). At wide open throttle, vacuum drops and pressure increases, so voltage rises
(approximately 4.5V).
Q6: Technician A says the PCM enters closed loop operation when the oxygen sensor reaches
operating temperature. Technician B says the PCM enters closed loop operation when the engine
coolant reaches a predetermined temperature. Who is correct?
A. Technician A only
B. Technician B only
C. Both Technician A and Technician B
D. Neither Technician A nor Technician B
Answer: C
, Rationale: The PCM enters closed loop when both conditions are met: the O2 sensor must reach
operating temperature (typically 600°F) and the engine coolant must reach a minimum
temperature (typically 140–160°F).
Q7: A vehicle has a P0120 code set. What does this code indicate?
A. Throttle position sensor circuit malfunction
B. Engine coolant temperature sensor circuit malfunction
C. Intake air temperature sensor circuit malfunction
D. Oxygen sensor circuit malfunction
Answer: A
Rationale: P0120 is defined as "Throttle/Pedal Position Sensor/Switch 'A' Circuit." This code is
set when the PCM detects an out-of-range signal from the throttle position sensor.
Q8: A technician is checking a throttle position sensor with a scan tool. The TPS voltage reading
jumps erratically when the throttle is slowly opened. What does this indicate?
A. The TPS is functioning correctly
B. The TPS has a dead spot or erratic signal
C. The PCM is faulty
D. The throttle cable is binding
Answer: B
Rationale: An erratic or jumpy TPS signal indicates a worn resistive element or dirty contacts
inside the sensor. The TPS should be replaced.
Q9: Technician A says the PCM uses the vehicle speed sensor (VSS) to control transmission shift
points. Technician B says the PCM uses the VSS for cruise control operation. Who is correct?
A. Technician A only
B. Technician B only
C. Both Technician A and Technician B
D. Neither Technician A nor Technician B
Answer: C
Rationale: The VSS provides vehicle speed data to the PCM, which uses it for multiple functions
including transmission shift scheduling, cruise control, speedometer operation, and torque
converter clutch engagement.
