The friction material left on at least one brake pad has been measured or judged below 1.5mm. That's the point where there isn't enough material left to guarantee the pad will still be doing its job before your next service, and it's also the point where the backing plate starts getting close to the disc.
Wording as it commonly appears on an MOT certificate: “Brake pad(s) less than 1.5mm thick”.
What does it mean?
The friction material left on at least one brake pad has been measured or judged below 1.5mm. That's the point where there isn't enough material left to guarantee the pad will still be doing its job before your next service, and it's also the point where the backing plate starts getting close to the disc.
How serious is it?
Usually recorded as: Major. The tester assesses the actual vehicle on the day, so your certificate is what counts.
What normally causes it?
- Normal wear — front pads on a typical UK car are usually good for somewhere between 25,000 and 40,000 miles depending on how and where you drive
- A sticking caliper slide pin holding one pad against the disc, which wears that pad much faster than its partner
- A seized handbrake mechanism on the rear, keeping the shoes or pads dragging
- Cheap pads fitted previously that wear far quicker than the original spec
What a mechanic would check
I'd get the wheel off and measure the material on both pads on that axle, not just the one that failed. If one side is noticeably thinner than the other, the pad isn't the problem — the caliper is. I'd also check the disc thickness and lip at the same time, because there's no sense fitting new pads to a disc that's near its minimum.
What might need replacing
- Brake pads on that axle (always replaced in axle sets, never one side)
- Discs as well, if they're worn, lipped or below minimum thickness
- Caliper slide pins cleaned and re-greased, or a caliper if it's seized
Can you still drive it?
This is recorded as a failure, so the car isn't roadworthy on that basis and shouldn't be used on the road until it's put right. Even before the MOT result, pads that low can go metal-to-metal quickly and start damaging the discs.
Repair cost
Varies a lot by vehicle. A set of pads on a small hatchback is one of the cheapest jobs on a car; pads and discs on a large SUV or a car with electronic parking brake calipers is a different conversation. Get the discs measured before you buy parts.
Before the retest
Brake work is usually done in axle pairs — pads and discs are replaced on both sides of the same axle so the car pulls up straight on the roller tester. After new pads or discs, drive gently for the first hundred miles or so if you can, because brakes need bedding in before they reach full efficiency. Keep the old parts or the invoice; a tester will not ask for them, but they settle any argument about what was actually replaced.
Retest rules
If the vehicle stays at the test centre for repair and is retested within 10 working days, a partial retest is often free; some items qualify for a free retest if you bring the car back by the end of the next working day. The exact conditions are set out on GOV.UK, so confirm with the test centre before you leave. A major or dangerous failure means the car cannot legally be driven away unless the previous MOT is still valid and nothing dangerous was recorded — check your certificate first.
Related help
More brakes failures · MOT failure decoder · Ask a mechanic about your certificate
This is general guidance from a UK mechanic, not a substitute for a physical inspection. Only the tester who inspected your vehicle can confirm what was recorded and why.