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ADAS Warning Lights Explained

When an ADAS warning light appears on your dashboard, it means one or more safety systems have detected a fault. Some warnings are critical and require immediate attention. Others indicate a system that needs recalibration.

This guide explains the most common ADAS warnings, what they mean, and what action to take.

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ADAS Warning Lights Explained

Common ADAS Dashboard Warnings

ADAS warning lights vary by manufacturer, but most follow a similar pattern. Amber warnings indicate a system fault that should be investigated. Red warnings indicate a critical safety issue that requires immediate attention.

Forward Collision Warning Light

This warning — usually shown as a car with impact lines or an exclamation mark — indicates the forward collision alert or automatic emergency braking system has a fault. Common causes include a dirty or misaligned windscreen camera, a faulty radar module, or calibration loss after windscreen replacement.

What to do: the vehicle is drivable, but automatic emergency braking may not function. Avoid motorway driving if possible and book a calibration check. If the windscreen was recently replaced, calibration is almost certainly needed.

Lane Departure Warning Light

Shown as a car drifting between lane markings, this warning means the lane departure warning or lane keeping assist system is not functioning. The most common cause is a windscreen camera that needs recalibration — especially after glass replacement.

What to do: the lane departure system will not alert you or correct your steering if you drift out of lane. This is an advisory feature, so the vehicle remains safe to drive, but you lose an important safety net. Book a camera calibration.

Blind Spot Monitoring Warning

This warning — typically shown as a vehicle icon with radar waves — indicates the blind spot detection system has a fault. Common causes include rear bumper removal, sensor damage from a rear impact, or wiring issues after body shop repairs.

What to do: the blind spot indicators in your door mirrors will not light up when vehicles are alongside. Use manual mirror and shoulder checks until the system is recalibrated. This requires radar calibration, not camera calibration.

Adaptive Cruise Control Warning

When ACC is unavailable, you will usually see a warning message or icon indicating the system is deactivated. This can be caused by a dirty or blocked radar sensor (common in winter), a misaligned radar after bumper work, or a genuine sensor fault.

What to do: first, check whether the radar sensor area (usually behind the front grille badge) is clean and free of ice or mud. If cleaning does not resolve the warning, the radar likely needs recalibration or diagnostic investigation.

Parking Sensor or Surround-View Warning

Persistent beeping, incorrect distance readings, or a surround-view camera showing a distorted image all indicate calibration or sensor faults. Common after bumper replacement, respray, or parking impact.

What to do: parking sensor faults are not a safety-critical issue at driving speed but can lead to parking collisions. If sensors were recently replaced or the bumper was repainted, calibration is likely needed.

Have an ADAS warning light on your dashboard? Submit your vehicle details and we will identify which systems need attention.

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ADAS Warning Lights Explained — Common Questions

Answers to frequently asked questions on this topic

Technically, a diagnostic tool can clear the fault code and turn off the warning light. However, this does not fix the underlying problem — the sensor remains misaligned or faulty. The warning will likely return, and in the meantime, the safety system is not functioning correctly. Always address the root cause rather than just clearing the code.