Automotive Service Technician (310S) — Red Seal
597 practice questions
Also known as: 310S, auto mechanic, car mechanic. In Ontario this is a compulsory certified trade (310S).
Practice questions for the Automotive Service Technician (Red Seal) exam, organized by Red Seal Occupational Standard (RSOS) section. 597 questions are available across 8 sections. Written to the Red Seal standard.
Practice Automotive Service Technician (Red Seal) free →
Sections (RSOS blocks)
| Section | RSOS block | Exam weight | Questions |
|---|---|---|---|
| A | Performs common occupational skills | 7% | 43 |
| B | Diagnoses and repairs engine and engine support systems | 17% | 106 |
| C | Diagnoses and repairs vehicle module communications systems | 10% | 58 |
| D | Diagnoses and repairs driveline systems | 14% | 82 |
| E | Diagnoses and repairs electrical and comfort control systems | 18% | 109 |
| F | Diagnoses and repairs steering, suspension, braking and control systems, tires, hubs and wheel bearings | 19% | 109 |
| G | Diagnoses and repairs restraint systems, body components, accessories and trim | 8% | 47 |
| H | Diagnoses and repairs hybrid and electric vehicle (EV) systems | 7% | 43 |
Mock exams are composed to match the official weightings above exactly — the question counts per section don't need to match 1:1.
Practice mock exam
The full practice mock for this trade is 125 questions, a 240-minute time limit, scored against a 70% pass line — the same question style used throughout this bank.
Sample questions
Performs common occupational skills
Service information specifies a torque-to-yield procedure for a cylinder head fastener. What does this require?
- Tighten to the listed torque value only, then stop
- Tighten progressively until the head gasket visibly seats
- Tighten until the click wrench releases three consecutive times
- Torque to specification, then turn through the specified angle
A torque-to-yield procedure tightens a fastener to a specified initial torque and then applies a defined further rotation angle that intentionally stretches the bolt into its yield range to produce a consistent clamping load. Stopping at the torque step alone leaves the bolt outside its designed clamp range. Repeated click releases do not provide angular control and do not load the bolt to yield. Visual seating of a gasket is not a torque procedure and is sensitive to surface friction. The procedure ordinarily requires single-use replacement of the fastener.
RSOS 2023 | A-2.02 Uses fasteners, tubing, hoses and fittings
Diagnoses and repairs engine and engine support systems
Which test best confirms a hairline external cooling-system leak that only weeps when the engine is hot?
- Add UV dye and use a black light during a long dark-bay idle
- Pressurize the warm cooling system to the rated cap pressure
- Squeeze the upper radiator hose and watch the surge tank level
- Run the engine to operating temperature with the cap off
Pressurizing a warm cooling system to the rated cap value reproduces the operating pressure and brings out hairline weeps at gaskets, hoses, and casting cracks where the leak only opens under combined heat and pressure. UV dye is useful but typically requires running the system long enough to circulate and may miss small intermittent weeps. Squeezing the upper hose is a coarse aeration check, not a leak test. Running with the cap off depressurizes the system, hides the leak, and risks coolant ejection. The pressure test reproduces field conditions in a controlled way.
RSOS 2023 | B-4.01 Diagnoses cooling systems
Diagnoses and repairs vehicle module communications systems
Why is freeze-frame data captured at the moment a code matures more valuable than live data captured later?
- It contains the manufacturer recommended repair procedure for the code
- It overrides the live data stream with corrected sensor values
- It is encrypted and proves the customer has not cleared codes
- It records the engine operating conditions present when the fault set
Freeze-frame data is a snapshot of the operating conditions - engine speed, load, coolant temperature, fuel trim, and similar parameters - at the moment the controller matured the code. It lets the technician reproduce conditions on a road test, or interpret the code in context, even if the fault is intermittent and not present now. It is not a correction to live data, not a tamper seal, and does not contain repair procedures. Reading freeze-frame before clearing codes is a standing practice because clearing the code can erase the snapshot.
RSOS 2023 | C-10.02 Monitors data
Trade Report
Wages by province, real job outlook, the Red Seal path, and exam weightings for Automotive Service Technician (Red Seal) — sourced and dated.
Read the Automotive Service Technician (Red Seal) Trade Report →