Brake-system warning
A red brake warning that stays on, or appears while riding, means the braking system needs checking before you ride any further.
Last reviewed: 16 October 2026 · Exact behaviour varies by make, model and year
Normal behaviour
On bikes that have a brake warning symbol it usually lights briefly during the ignition self-test. On some scooters and three-wheelers the same symbol confirms a parking brake is applied. Many motorcycles do not have a dedicated brake warning at all and rely on the ABS symbol and the rider's own checks, so look up your own dashboard in the handbook.
Possible fault
If the light stays on or comes on while riding, the most common cause is a low brake-fluid level in a reservoir. Fluid level falls slowly as pads wear, so the light can simply mean the pads are near the end of their life — but it can also mean fluid is leaking from a line, seal or caliper, which is dangerous. On linked or combined braking systems the light can also signal a fault in that system.
What to do
Stop somewhere safe. With the bike upright, look at the brake-fluid reservoir sight glass or level marks for the front and rear systems, and look for wetness around calipers, hoses and the master cylinders. If a level is low and there is no leak, the pads may be worn; arrange a pad and fluid check before riding further. If you can see a leak, the lever or pedal feels spongy or travels further than usual, or stopping power has changed at all, do not ride — arrange recovery. Do not top the fluid up and carry on: topping up hides the symptom, not the cause.
Possible causes
- •Brake fluid below the minimum mark because the pads are worn
- •Fluid leak from a hose, union, caliper seal or master cylinder
- •Parking brake applied (scooters and three-wheelers)
- •Fluid-level sensor, float or wiring fault
- •Fault in a linked or combined braking system
- •Air in the system after recent work, or old fluid that has absorbed water
When not to ride
Do not ride with a brake warning on if the lever or pedal feels different, fluid is visibly leaking, the warning appears together with the ABS light, or you cannot find the reason. Braking faults are not something to "nurse home".
Sources
- GOV.UK — Motorcycle MOT inspection manual, Section 1: brakeshttps://www.gov.uk/guidance/mot-inspection-manual-for-motorcycles/1-brakes
- The Highway Code — Annex 6: vehicle maintenance, safety and securityhttps://www.gov.uk/guidance/the-highway-code/annex-6-vehicle-maintenance-safety-and-security
- Your motorcycle's owner's handbook (authoritative for your model)https://www.gov.uk/topic/transport/motorcycles