Modern vehicles are increasingly fitted with Advanced Driver Assistance Systems (ADAS) designed to make driving safer and more efficient. These technologies — such as lane-keeping assist, adaptive cruise control, and automatic emergency braking — rely on sensors and cameras to function correctly. However, when these systems fail or malfunction, they can affect the outcome of your MOT test.

Understanding how ADAS features are checked during MOTs can help drivers in the UK maintain their vehicles properly and avoid costly failures.

For quick MOT status and history checks, visit Check MOT.

What Are Advanced Driver Assistance Systems (ADAS)?

ADAS refers to electronic systems that assist drivers with tasks like braking, steering, and parking. Some of the most common ADAS features include:

• Lane Departure Warning (LDW) and Lane Keep Assist (LKA)
• Adaptive Cruise Control (ACC)
• Automatic Emergency Braking (AEB)
• Blind Spot Detection (BSD)
• Traffic Sign Recognition (TSR)
• Parking Sensors and 360° Cameras

These systems are designed to reduce human error and prevent accidents — but they depend heavily on precise calibration and functioning sensors.

Are ADAS Systems Checked in MOT Tests?

While there isn’t a dedicated section of the MOT test solely for ADAS, their failures can still indirectly cause a MOT failure. If an ADAS system fault results in dashboard warning lights, malfunction indicators, or safety concerns, the vehicle may fail.

For example:

• Warning Lights: If an AEB or lane assist warning light is illuminated, it’s considered a fault under MOT guidelines.
• Windscreen Obstruction: Cameras and sensors mounted behind the windscreen must have a clear, unobstructed view. A cracked or tinted windscreen may result in an advisory or failure.
• Calibration Issues: After repairs or windscreen replacements, sensors must be recalibrated. Uncalibrated ADAS can affect performance and safety, raising potential MOT issues.

Common ADAS-Related MOT Failures

1. Faulty Warning Lights – A malfunction indicator light (MIL) for braking or stability control is an immediate fail.
2. Sensor Damage or Misalignment – Bumps, poor repairs, or windscreen replacements can throw off calibration.
3. Camera Blockages – Dirt or stickers on the windscreen can interfere with ADAS cameras.
4. Software Errors – In some cases, outdated software may cause intermittent ADAS faults.

Regular servicing and calibration checks are crucial to avoid these problems surfacing during an MOT inspection.

How to Prevent ADAS Failures Before MOT

To reduce the risk of MOT issues related to ADAS:

• Get ADAS systems checked after any repair, accident, or windscreen change.
• Keep sensors and cameras clean and clear.
• Ensure all warning lights are resolved before booking your MOT.
• Use authorised service centres for calibration work.

A proactive maintenance routine helps ensure that your ADAS features perform correctly and your vehicle passes its MOT first time.

FAQs

1. Do all cars have ADAS systems checked during MOTs?

Not directly. MOT testers inspect whether dashboard warning lights are active and if safety systems appear faulty.

2. Can a faulty ADAS sensor cause an MOT failure?

Yes, if it triggers a warning light or compromises key safety functions like braking or steering assistance.

3. How often should I recalibrate ADAS sensors?

Sensors should be recalibrated after any event that could affect their position — such as tyre changes, wheel alignment, or windscreen replacement.

4. Can I still drive if my ADAS system shows a fault?

It’s legal but not advisable. Malfunctioning safety systems may affect braking or stability, and could lead to an MOT failure later.

Proper care of Advanced Driver Assistance Systems ensures both your safety and MOT compliance. Use Check MOT to stay on top of your vehicle’s MOT history and plan ahead to avoid surprises at your next test.