Seeing the ABS light appear on your dashboard can be unsettling, but understanding what it means takes most of the worry out of it. Here is exactly what the ABS warning light means, the common causes, and what to do if it comes on.
What Does the ABS Warning Light Mean?
The ABS warning light usually appears as the letters “ABS” inside a circle, typically shown in amber or yellow on your dashboard. It briefly illuminates during a routine system check when you start the car. If it stays on while driving, it means the Anti-lock Braking System has detected a fault and disabled the anti-skid function, though your normal brakes will still work.
Common Causes of the ABS Warning Light
- Faulty wheel speed sensor: the most common cause. Sensors near the wheel hubs are regularly exposed to heat, water and road debris, which can damage them over time.
- Low brake fluid: as brake pads wear down, more fluid is needed in the system, which can lower the reservoir level enough to trigger the light.
- Damaged wiring or corroded connectors: wear near the wheel hubs can disrupt communication between the ABS module and sensors.
- Blown fuse: a simple electrical fault can shut the whole system down.
- Faulty ABS module or hydraulic pump: a less common but more serious cause, usually needing specialist diagnosis.
What to Do If the ABS Light Comes On
- Stay calm. Your regular brakes will still work; only the anti-lock, anti-skid function is affected.
- Check your brake fluid level and top up if it’s low.
- Restart the car. This sometimes resets the system if the light was triggered by a temporary glitch.
- Drive cautiously if you must drive, avoiding hard braking and slippery roads.
- Book a diagnostic check as soon as possible if the light stays on.
Is It Safe to Drive With the ABS Light On?
Yes, in most cases, since your standard braking system remains fully functional. However, if the ABS light and the main brake warning light come on together, this signals a more serious problem and you should stop driving and seek assistance immediately.
Does the ABS Light Affect Your MOT?
Yes. An illuminated ABS warning light during an MOT test is likely to result in a fail, since ABS is a checked safety system on any vehicle built with it fitted as standard. It is worth fixing before booking your MOT to avoid an automatic failure.
How Much Does It Cost to Fix an ABS Fault?
A faulty wheel speed sensor, the most common cause, typically costs around £70 to replace in the UK. More complex faults involving the ABS module or hydraulic pump can cost considerably more, so a proper diagnostic check is worth having before agreeing to any repair.
Frequently Asked Questions
Can I still brake normally if the ABS light is on?
Yes, your normal braking system continues to work. You simply lose the anti-lock function that helps prevent wheel lock-up during hard braking.
Will the ABS light cause an MOT failure?
Yes, an illuminated ABS warning light will typically result in an MOT failure, so it should be diagnosed and fixed before your test.
What’s the most common reason the ABS light comes on?
A faulty or dirty wheel speed sensor is the most common cause, often due to exposure to road debris, water and heat near the wheel hub.
Related reading: keeping your braking system in top shape? See our guide on the safest cars in the UK and their safety features.
Written by the Apriliapartsbuyer editorial team, covering UK car maintenance and safety guides.
