Class 5 Theory Test study materials
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Pre-start defect, RUC shortfall, expiring CoF and an overweight axle

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Pre-start defect, RUC shortfall, expiring CoF and an overweight axle

It is 5:40 a.m. and a driver is doing the pre-start check on a 2014 rigid curtain-sider with a CoF label showing expiry in three days. While draining the air tanks the driver notices a chafed air line running to the trailer coupling, with the outer casing worn through to the braid. The truck has 12 km left on its RUC licence, and the run is 140 km. The docket shows the load is 300 kg over the permitted steer-axle limit, with the drive axles well under. The dispatcher says the customer's crew finishes at 2 p.m. and that 'the air line held all day yesterday'. The driver holds a Class 5 licence and there is no mechanic on site until 7:30 a.m. The first 40 km is a steep, winding hill road and rain is forecast from 9 a.m.

1. Rank the four issues and say which one stops the truck moving right now.

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The chafed air line is the one that stops the truck now. It is a brake defect on the trailer supply; if it lets go, the trailer loses air, the spring brakes apply and the unit can jackknife at speed. The overweight steer axle also stops it: mass limits are legal limits, not targets, and 300 kg over is an offence as well as a steering and tyre problem. Those two must be fixed before the wheels turn. The RUC shortfall (12 km against 140 km) is easily fixed online before departure, so it is a paperwork task rather than a roadblock. The CoF is valid for three more days, so it does not stop today's run, but it must be booked and the vehicle off the road before it lapses.

2. What has to happen before the truck leaves, and what can be handled on the road?

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Before departure: the air line is replaced by a competent person, not taped, with the repair recorded and the trailer brakes checked. The load is re-worked so the steer axle is under its limit while the drive axles and gross mass stay legal, then re-weighed if a weighbridge is available; if it cannot be repositioned legally, some load comes off. Enough RUC for 140 km plus a margin is bought before leaving, and the CoF inspection is booked. On the road: re-check load restraint and feel tyre and hub temperatures at the first stop, and expect the 9 a.m. rain to make the hill section slower. Changing conditions are a reason to replan the timing, not a reason to skip a fix.

3. If the truck went out anyway and crashed, who carries the responsibility, and what should the driver do now?

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The driver signs off the pre-start and is responsible for not moving a defective vehicle; the operator is responsible for the maintenance system and for not pressuring a driver to run a known defect. Both would face health and safety and traffic charges, and the insurer would likely decline the claim because a known brake defect was left unrepaired. 'It held yesterday' is not a diagnosis. The driver should record the defect, time and photographs, refuse in writing, and log the load and RUC issues as well, so the paper trail shows the problems were identified and dealt with rather than hidden.