Alberta Automotive Service Technician
Qualification Examination Questions
And Correct Answers (Verified Answers)
Plus Rationales 2026 Q&A | Instant
Download Pdf
1. A 2022 vehicle equipped with a start-stop system experiences an
intermittent no-crank condition with all dashboard warning lights
illuminating normally. The battery tests at 12.4 volts with a state of charge
of 75%. During the start-stop event, the engine fails to restart, and the
starter relay clicks rapidly. Which of the following is the most likely root
cause of this intermittent failure?
A. A faulty starter motor armature
B. A defective engine coolant temperature sensor
C. An insufficient battery state of health with high internal resistance
D. A stuck closed purge valve
Answer: C
*Rationale: In start-stop systems, the battery must maintain a high state of
health to support frequent restarts. A static voltage test is insufficient; the
battery may show adequate voltage but fail under load due to high internal
resistance, leading to voltage drop during cranking and rapid relay cycling.
2. During an oscilloscope test of a crankshaft position sensor on a direct
injection engine, the technician observes a consistent AC sine wave pattern
at idle, but the signal amplitude drops significantly at 3000 RPM. What is
the most likely interpretation of this waveform?
A. Normal operation due to increased engine speed
B. An air gap that is too large between the sensor and reluctor wheel
C. A short circuit to ground in the sensor signal wire
, D. Excessive resistance in the sensor's reference voltage circuit
Answer: B
*Rationale: A crankshaft position sensor's output voltage (amplitude)
increases with engine speed if the air gap is correct. A drop in amplitude at
higher speeds indicates the magnetic field is weak, often caused by an
excessive air gap, preventing the sensor from generating sufficient voltage
for the PCM to detect the signal.
3. A technician is diagnosing a vehicle with a P0300 random misfire code. The
fuel trim values show Long Term Fuel Trim (LTFT) at +18% on Bank 1 and
+5% on Bank 2. A propane enrichment test causes a significant increase in
engine RPM on Bank 1 but not Bank 2. What is the most accurate
conclusion?
A. The oxygen sensor on Bank 1 is slow to respond
B. There is a vacuum leak affecting Bank 1
C. The fuel injectors on Bank 1 are restricted
D. The mass airflow sensor is providing false data
Answer: B
*Rationale: A positive fuel trim indicates the PCM is adding fuel to
compensate for a lean condition. A vacuum leak introduces unmetered air.
Propane enrichment adding fuel to the mixture raises the RPM, confirming
the leak on Bank 1. If injectors were restricted, RPM would likely decrease
with propane as the mixture became too rich.
4. When performing a cylinder leakage test on a 6.7L diesel engine, the
technician hears air escaping from the oil filler cap. The cylinder being
tested is at Top Dead Center (TDC) on the compression stroke. What does
this symptom indicate?
A. A worn exhaust valve
B. A broken piston ring or worn cylinder bore
C. A leaking head gasket to the cooling system
D. A stuck intake valve
Answer: B
*Rationale: Air escaping into the crankcase, evidenced by noise at the oil
, filler cap, indicates leakage past the piston rings into the crankcase. This is
caused by worn rings, a scored cylinder wall, or a cracked piston.
5. A vehicle equipped with an electronic throttle control (ETC) system has a
complaint of reduced engine power. A scan tool shows that the Accelerator
Pedal Position (APP) sensor indicates 100% when the pedal is fully
depressed, but the Throttle Position (TP) sensor indicates only 65%. The
technician commands the throttle to 100% using the scan tool's bi-
directional controls, and the throttle plate moves fully open. What is the
most likely cause?
A. A faulty TP sensor
B. A stretched throttle cable
C. An electrical fault in the APP sensor circuit
D. The PCM is limiting torque due to a traction control event
Answer: D
*Rationale: Since the throttle can be commanded to full opening via the
scan tool, the throttle actuator and motor are functioning. The discrepancy
between APP and TP indicates the PCM is actively overriding the driver's
demand, likely due to a torque management strategy such as traction
control or stability control intervention.
6. A customer complains that the air conditioning system blows cold air for the
first 15 minutes of driving, then gradually becomes warm. The compressor
engages and disengages normally at idle. The high-side and low-side
pressures are normal when the system is operating. Which of the following
is the most likely cause of this gradual loss of cooling?
A. A restricted cabin air filter
B. Moisture freezing at the expansion valve
C. A faulty ambient air temperature sensor
D. An overcharged system
Answer: B
*Rationale: Moisture in the system can freeze at the expansion valve orifice,
blocking refrigerant flow. This typically occurs after the system has been
, running for a while, as the temperature drops below freezing at the valve.
When the system is shut off, the ice melts, and cooling resumes temporarily.
7. A 4L60-E transmission slips during the 2-3 upshift. The fluid level is correct,
and the fluid is not burnt. The technician checks line pressure and finds it to
be low only in 3rd and 4th gears. Which of the following components is
most likely at fault?
A. The torque converter
B. The 2-3 shift solenoid
C. The 3-4 clutch pack
D. The valve body accumulator for 3rd gear
Answer: D
*Rationale: Low line pressure specific to certain gears often indicates a leak
in the hydraulic circuit for those gears. The 3rd gear accumulator valve or
piston in the valve body controls the apply rate for the 3-4 clutch. If it is
leaking, line pressure will drop when 3rd or 4th gear is engaged.
8. An automotive technician is diagnosing a vehicle with a "Service Brake
Assist" message on the dash. The brake pedal feels hard and requires
excessive effort to stop the vehicle. The vacuum pump is running
continuously. What is the most likely cause?
A. A faulty brake light switch
B. A leaking vacuum booster diaphragm
C. A restricted brake hose
D. A faulty wheel speed sensor
Answer: B
*Rationale: A hard brake pedal indicates a loss of vacuum assist. If the
vacuum pump runs continuously, it is trying to compensate for a vacuum
leak. The most common source of such a leak is a ruptured diaphragm
inside the brake booster.
9. A vehicle's steering wheel has excessive free play, and the vehicle wanders
on the highway. The tie rod ends and ball joints are found to be in good
condition. During an inspection, the technician notices that the steering
Qualification Examination Questions
And Correct Answers (Verified Answers)
Plus Rationales 2026 Q&A | Instant
Download Pdf
1. A 2022 vehicle equipped with a start-stop system experiences an
intermittent no-crank condition with all dashboard warning lights
illuminating normally. The battery tests at 12.4 volts with a state of charge
of 75%. During the start-stop event, the engine fails to restart, and the
starter relay clicks rapidly. Which of the following is the most likely root
cause of this intermittent failure?
A. A faulty starter motor armature
B. A defective engine coolant temperature sensor
C. An insufficient battery state of health with high internal resistance
D. A stuck closed purge valve
Answer: C
*Rationale: In start-stop systems, the battery must maintain a high state of
health to support frequent restarts. A static voltage test is insufficient; the
battery may show adequate voltage but fail under load due to high internal
resistance, leading to voltage drop during cranking and rapid relay cycling.
2. During an oscilloscope test of a crankshaft position sensor on a direct
injection engine, the technician observes a consistent AC sine wave pattern
at idle, but the signal amplitude drops significantly at 3000 RPM. What is
the most likely interpretation of this waveform?
A. Normal operation due to increased engine speed
B. An air gap that is too large between the sensor and reluctor wheel
C. A short circuit to ground in the sensor signal wire
, D. Excessive resistance in the sensor's reference voltage circuit
Answer: B
*Rationale: A crankshaft position sensor's output voltage (amplitude)
increases with engine speed if the air gap is correct. A drop in amplitude at
higher speeds indicates the magnetic field is weak, often caused by an
excessive air gap, preventing the sensor from generating sufficient voltage
for the PCM to detect the signal.
3. A technician is diagnosing a vehicle with a P0300 random misfire code. The
fuel trim values show Long Term Fuel Trim (LTFT) at +18% on Bank 1 and
+5% on Bank 2. A propane enrichment test causes a significant increase in
engine RPM on Bank 1 but not Bank 2. What is the most accurate
conclusion?
A. The oxygen sensor on Bank 1 is slow to respond
B. There is a vacuum leak affecting Bank 1
C. The fuel injectors on Bank 1 are restricted
D. The mass airflow sensor is providing false data
Answer: B
*Rationale: A positive fuel trim indicates the PCM is adding fuel to
compensate for a lean condition. A vacuum leak introduces unmetered air.
Propane enrichment adding fuel to the mixture raises the RPM, confirming
the leak on Bank 1. If injectors were restricted, RPM would likely decrease
with propane as the mixture became too rich.
4. When performing a cylinder leakage test on a 6.7L diesel engine, the
technician hears air escaping from the oil filler cap. The cylinder being
tested is at Top Dead Center (TDC) on the compression stroke. What does
this symptom indicate?
A. A worn exhaust valve
B. A broken piston ring or worn cylinder bore
C. A leaking head gasket to the cooling system
D. A stuck intake valve
Answer: B
*Rationale: Air escaping into the crankcase, evidenced by noise at the oil
, filler cap, indicates leakage past the piston rings into the crankcase. This is
caused by worn rings, a scored cylinder wall, or a cracked piston.
5. A vehicle equipped with an electronic throttle control (ETC) system has a
complaint of reduced engine power. A scan tool shows that the Accelerator
Pedal Position (APP) sensor indicates 100% when the pedal is fully
depressed, but the Throttle Position (TP) sensor indicates only 65%. The
technician commands the throttle to 100% using the scan tool's bi-
directional controls, and the throttle plate moves fully open. What is the
most likely cause?
A. A faulty TP sensor
B. A stretched throttle cable
C. An electrical fault in the APP sensor circuit
D. The PCM is limiting torque due to a traction control event
Answer: D
*Rationale: Since the throttle can be commanded to full opening via the
scan tool, the throttle actuator and motor are functioning. The discrepancy
between APP and TP indicates the PCM is actively overriding the driver's
demand, likely due to a torque management strategy such as traction
control or stability control intervention.
6. A customer complains that the air conditioning system blows cold air for the
first 15 minutes of driving, then gradually becomes warm. The compressor
engages and disengages normally at idle. The high-side and low-side
pressures are normal when the system is operating. Which of the following
is the most likely cause of this gradual loss of cooling?
A. A restricted cabin air filter
B. Moisture freezing at the expansion valve
C. A faulty ambient air temperature sensor
D. An overcharged system
Answer: B
*Rationale: Moisture in the system can freeze at the expansion valve orifice,
blocking refrigerant flow. This typically occurs after the system has been
, running for a while, as the temperature drops below freezing at the valve.
When the system is shut off, the ice melts, and cooling resumes temporarily.
7. A 4L60-E transmission slips during the 2-3 upshift. The fluid level is correct,
and the fluid is not burnt. The technician checks line pressure and finds it to
be low only in 3rd and 4th gears. Which of the following components is
most likely at fault?
A. The torque converter
B. The 2-3 shift solenoid
C. The 3-4 clutch pack
D. The valve body accumulator for 3rd gear
Answer: D
*Rationale: Low line pressure specific to certain gears often indicates a leak
in the hydraulic circuit for those gears. The 3rd gear accumulator valve or
piston in the valve body controls the apply rate for the 3-4 clutch. If it is
leaking, line pressure will drop when 3rd or 4th gear is engaged.
8. An automotive technician is diagnosing a vehicle with a "Service Brake
Assist" message on the dash. The brake pedal feels hard and requires
excessive effort to stop the vehicle. The vacuum pump is running
continuously. What is the most likely cause?
A. A faulty brake light switch
B. A leaking vacuum booster diaphragm
C. A restricted brake hose
D. A faulty wheel speed sensor
Answer: B
*Rationale: A hard brake pedal indicates a loss of vacuum assist. If the
vacuum pump runs continuously, it is trying to compensate for a vacuum
leak. The most common source of such a leak is a ruptured diaphragm
inside the brake booster.
9. A vehicle's steering wheel has excessive free play, and the vehicle wanders
on the highway. The tie rod ends and ball joints are found to be in good
condition. During an inspection, the technician notices that the steering
