Air-pressure warning on a school run
You are about to take out a 12-metre coach for a 07:30 school run. On start-up the low air-pressure warning buzzer sounds and the gauge shows 5.8 bar. After two minutes idling the buzzer stops and the gauge reads 7.2 bar. You switch off and the gauge falls to 6.1 bar in 8 minutes, with a faint hiss near the rear offside wheel. The footbrake pedal feels firm but the first application travels further than usual. The depot is 600 m away down a side road; the school is 14 miles away. It is raining and the vehicle is due a PMI in 10 days. 42 children are waiting.
1. Decide whether to take the vehicle out and state your immediate actions.
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This is a brake-system defect, not a nuisance warning. The low-pressure buzzer stopping only shows the compressor has built pressure; the fall from 7.2 to 6.1 bar in 8 minutes with a hiss indicates a leak, and the longer pedal travel points to insufficient or inconsistent braking. Do not take the vehicle out with 42 children. Park safely, switch off, chock wheels, inform the transport manager and workshop, and record the defect. It needs assessment by a competent person before any passenger service.
2. Can you drive the 600 m to the depot?
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No. A 600 m move on a public road is still a journey with defective brakes, and the defect is safety-critical. Use a recovery vehicle or have an engineer attend; if movement is unavoidable inside the depot, it should be at walking pace with a banksman and written authorisation, not on the road. The school run should be covered by a replacement vehicle or cancelled. Do not let the short distance or the rain influence the decision.
3. What must you record and tell the school?
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Record the symptoms, gauge readings, time and your decision in the defect book and on the daily walk-round record. Tell the school promptly that the vehicle is off the road and give the replacement arrangement. The operator must arrange repair and record the rectification. Keep the defect record available for inspection; a safety-critical brake defect should not be cleared without a competent person's confirmation.