Brake fluid leak
How it can appear on an MOT certificate
- “Brake fluid leaking”
- “Brake system fluid leak”
What it is
Brake fluid transmits the pressure from the brake pedal to each wheel. It sits in a sealed system, so any leak means a fault somewhere in the pipes, hoses, calipers or cylinders.
Why it matters
Losing fluid reduces braking and can lead to the pedal going to the floor. Any brake fluid leak needs fixing before the car is driven.
What to check when viewing a car
Look at the fluid reservoir level under the bonnet, and for damp patches around the wheels and on the ground where the car is parked.
Has the car you're looking at had this before?
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What the MOT categories mean
- Dangerous
- A direct and immediate risk to road safety, or a serious impact on the environment. The car fails and shouldn't be driven until it's repaired.
- Major
- It may affect the car's safety, put other road users at risk or harm the environment. The car fails and should be repaired straight away.
- Minor
- No significant effect on safety or the environment. The car passes, but it should be repaired as soon as possible.
- Advisory
- Something to keep an eye on that could need repairing in future. The car passes.
Related: brakes
- Brake pads wearing thin
- Brake discs worn, pitted or scored
- Brake pipe corroded
- Brake hose damaged or deteriorated
- Parking brake (handbrake) not working well enough
- Brakes pulling or uneven (imbalance)
Buying a used car?
General information about this type of MOT defect, not advice about a particular car. How serious it is depends on the car; have any car you're buying inspected by a qualified mechanic.