The three categories on the sheet
Since 2018 every defect is graded. Dangerous means the car must not be driven on the road at all, and driving it can bring a fine and points; you would need it recovered. Major means it failed and must be repaired before it can pass, but you may drive it away from the test station if your previous MOT is still valid and no dangerous defect is listed. Minor items are recorded but do not fail the car, and advisories are notes for next year — worth acting on early rather than ignoring.
You normally get 10 working days to repair and return for a retest at the same station. Bring the fail sheet with you; it is what ties the retest to the original test.
The usual suspects, and rough parts costs
Prices below are typical retail ranges for the part itself. Garages charge labour on top, and a seized bolt or a rusted brake line can turn a 30-minute job into a two-hour one. Always check current prices for your exact model.
Brakes — pads, discs and lines
Worn pads or a scored disc is one of the most common fails. A set of front pads is usually £20–£45, a pair of discs £60–£140 depending on size, and rear pads often a little less. Corroded brake pipes are a different matter: the pipe is cheap, the labour to run a new line is not.
Suspension — springs, shocks and bushes
A broken coil spring is a straight fail and one of the most frequent. A single replacement spring is typically £35–£70, but springs should be changed in pairs on the same axle. A leaking shock absorber runs £45–£150 per corner, and worn anti-roll bar bushes or drop links are usually under £25 a side.
Lighting and visibility
Bulbs and wiper blades are the cheapest fixes on the sheet: £5–£15 for a bulb, £10–£25 for a pair of blades. Washer jets that do not spray are often a blocked filter or a split hose rather than a new pump.
Tyres and wheels
A tyre below 1.6mm, a cut to the cords or a bulge is a fail. A replacement tyre in a common size is £60–£120 fitted, more for larger low-profile sizes. If the sheet mentions a distorted wheel or a leaking rim seal, that is wheel work rather than a tyre.
Exhausts, bearings and boots
A corroded back box is typically £50–£120. A noisy wheel bearing is £30–£80 for the part and is worth doing promptly because the noise masks other problems. A split CV boot is £10–£25 — replace it before the joint fails, because a full driveshaft is many times that.
Structural corrosion
Rust within 30cm of a suspension or seatbelt mounting point is not a parts job. That is welding, and it needs a body shop quote before you decide whether the car is worth keeping.