Vehicle Maintenance, Servicing and Troubleshooting
What the exam tests
Vehicle maintenance, servicing and troubleshooting covers preventive maintenance schedules, service checks, diagnostic logic and fault symptoms. Questions test whether you can move from symptom to cause without replacing parts blindly.
Core rules and concepts
- Preventive maintenance follows time or distance intervals: engine oil, filters, belts, coolant, brake fluid and tyre rotation.
- A service check includes fluid levels, leaks, tyre condition, brake wear, lights, battery and suspension.
- Troubleshooting should follow a sequence: verify the complaint, gather information, test, isolate the cause, repair and confirm.
- OBD codes point to a circuit or system; they do not always name the failed part.
- Wear patterns reveal alignment and suspension faults; tyre pressure affects wear and fuel consumption.
Worked example
A car cranks slowly and the battery rests at 12.4 V, about half state of charge. During cranking, battery voltage falls to 9.2 V. A load test confirms the battery cannot hold capacity, so it is replaced. If voltage had stayed above 10 V and cables were clean, the starter or engine mechanical drag would be checked next. The reasoning separates battery, connection and starter faults instead of guessing.
Traps that cost marks
- Replacing sensors because a code appears, without testing the circuit.
- Ignoring service intervals and fluid specifications.
- Diagnosing tyre wear without checking pressure, camber and toe.
- Skipping the final road test after repair.