Vehicle Maintenance, Servicing and Repair
This domain tests planned servicing, routine checks, fault diagnosis, repair quality and record keeping.
Maintenance types
- Preventive maintenance follows a schedule before failure.
- Predictive maintenance uses condition monitoring, such as oil analysis or vibration checks.
- Breakdown maintenance repairs after failure and is usually the most costly.
- Daily checks include oil level, coolant, brake fluid, tyre condition, lights and warning lamps.
- Service schedules usually cover engine oil and filter, air filter, spark plugs, belts, brake inspection and wheel alignment.
Repair practice
- Use the maker's torque figures and tighten in the specified sequence.
- Replace gaskets, seals and stretch bolts where specified.
- Read fault codes before replacing parts; clear codes only after the repair.
- Record the complaint, cause, correction and parts used.
- Road-test after safety-related work.
Worked example
A tyre is set to 30 psi cold. After a highway run the gauge reads 34 psi. The correct action is to leave it alone and recheck cold. Tyres heat up in service, so pressure rises; deflating a hot tyre to 30 psi would leave it underinflated when cold. The reasoning is that the specification is a cold pressure.
Traps
- Checking engine oil immediately after shutdown instead of allowing drain-back.
- Deflating hot tyres to the cold specification.
- Over-torquing wheel nuts or tightening them in a circle instead of a star pattern.
- Erasing fault codes without repairing the fault.
- Skipping the road test after brake or steering work.