Vehicle Mechanics and Technical Maintenance
Systems a candidate must understand
- Braking system: service brake, parking brake, retarder/endurance brake, ABS and EBS; how air pressure loss is indicated and what the warning means.
- Tyres: tread depth limits, pressure monitoring, signs of damage, matching and retreading rules, and the effect of under-inflation on heat and fuel use.
- Steering, suspension and coupling: fifth-wheel and drawbar coupling checks, safety devices, and the pre-departure walk-around.
- Lights and signalling, including mandatory lamps and their correct adjustment.
- Fluids and filters: engine oil, coolant, AdBlue for emissions control, and the consequences of ignoring dashboard warnings.
- Diagnostics: reading warning symbols and knowing which faults require an immediate stop.
Pre-departure checks
A systematic walk-around covers tyres, lights, brakes (including air build-up and leak test), coupling security, load restraints, mirrors, wipers, fluids and warning lamps. Record defects and report them; do not drive a vehicle with a defect that affects safety.
Traps in questions
- Confusing a warning lamp that permits a journey to a workshop with one that requires an immediate stop.
- Assuming ABS removes the need for correct brake balance or maintenance.
- Forgetting that under-inflated tyres overheat and can fail.
- Treating a minor defect as acceptable because the vehicle "still drives".
Worked example
If the air-pressure warning appears and pressure does not build to the specified level during the test, the vehicle is unroadworthy: do not move it. If a single side-marker lamp has failed, record it and have it repaired, but the defect is not in the same category. Sorting faults into "stop", "workshop soon" and "record and repair" is the key skill.