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Servicing and MOT

What is an MOT Test?

The annual road-safety, emissions and roadworthiness check required by UK law.

INSPECTION BAYMOT CHECKLightsBrakesTyresEmissionsSteeringPASS

Simplified animation — not to scale.

In plain English

An MOT (Ministry of Transport) test is a yearly inspection that every car over 3 years old in the UK must pass. A certified tester checks key safety and environmental items — lights, brakes, tyres, steering, suspension, seatbelts, exhaust emissions, mirrors, wipers, washers, horn and bodywork — to confirm the car meets the minimum legal standard to be driven on public roads. It is not a service: nothing is repaired or replaced, the car is only inspected. Pass and you get an MOT certificate valid for 12 months; fail and you cannot legally drive the car (except to a pre-booked repair or retest).

A simple analogy

"Think of the MOT as your car's annual health screening with the DVLA as the GP. It does not fix anything — it just tells you (and the government) whether the car is safe and clean enough to be on the road for another year. Like a medical check-up, turning up in better shape (bulbs working, screen wash topped up, tyres legal) massively improves your odds of a clean pass."

How it works

A tester runs through a fixed government checklist in roughly 45–60 minutes: visual checks, brake-roller tests, emissions sniffer on the exhaust, headlight beam alignment, and an underbody inspection on a ramp. Each item is marked Pass, Minor (advisory), Major (fail) or Dangerous (fail + must not be driven). Results are uploaded to the DVSA database in real time, so your MOT history is searchable online by registration number.

Signs of trouble

  • ⚠MOT due date approaching (check gov.uk with your reg)
  • ⚠Warning lights on the dashboard — these alone can cause a fail
  • ⚠Worn tyres below 1.6mm tread
  • ⚠Cracked or chipped windscreen in the driver's line of sight
  • ⚠Blown bulbs, hazy headlights or non-working indicators
  • ⚠Excessive exhaust smoke or rattling
  • ⚠Number plate dirty, damaged or wrong font
Rough UK cost

£30–£55 for the test; repairs to fix failures are extra and vary widely

Parts: £0 for the test itself if nothing fails
Labour: £54.85 maximum (government-capped) — many garages charge £30–£45

Always get a written quote. Prices vary by car, region, and parts brand.

Heads up: Carautonomy is for general guidance only. If your car is showing warning lights or behaving oddly, get it looked at by a qualified mechanic.

Keep exploring

Alternator
The on-board power station that keeps your battery topped up.
EGR Valve
A small valve that recycles exhaust gas to reduce emissions.
Starter Motor
The muscle that turns your engine over when you twist the key.

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A friendly note

Information here is general guidance, not a diagnosis. Always speak to a qualified mechanic before parting with cash.

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